Breakthrough in ambient light rejecting screen

[bud16415]

Edit 11-01-06
(This thread was started to show a factual scientific aspect of screen design involving projecting to a totally black screen surface. I crafted this post as a bit of a tease and was actually unaware that it would be viewed on Halloween day 2006. My intention was to bring a little fun into the science here and stimulate some thinking. Most viewing it enjoyed the process but some didn’t. It has been brought to my attention some newcomers could read this and attempt this as a real world solution to building a screen. That’s not the intent of the thread, the intent is to illustrate the concept of a neutral gray being used as a screen surface taken to an extreme limit. If you are new and want to learn more about neutral gray painted screens look to the links in my signature at the bottom of this post.)
(((( Like Myth Busters I must post this warning….. Don’t Try This At Home!!!!))))
:D :D :D


As many of you know I seldom start a new thread unless it’s a topic I believe has not been covered before. This is such a thread I believe.

I finished a prototype screen tonight and its ambient light performance is so superior to anything I have seen to date I had to take some screen shots and post them for the group to view. Please excuse the picture quality they were taken soon after completing the screen and I just threw in a couple DVD’s and looked for screen shots that had good light dark comparisons.

First let me explain the lighting conditions in my room for these shots. All room lights were on that’s a total of (8) 60 watt ceiling flood lights the closest 2 being 4 foot from the screen. in addition I added (2) 100 watt bare bulbs each side of the screen about 3 feet in front of the screen and 2 feet to the sides. The ceiling is a gloss white pegboard material.

The pictures were taken hand held and with cam set to auto, flash off. The screen was larger than the image and the black masking you see top and bottom was the DLP projector self masking. The projector is my Sharp XR10X running in echo mode.

I post these photos to show the deep black levels that are possible with this new DIY screen under the most severe ambient conditions I have ever subjected a screen shoot to. Notice while keeping these rich dark blacks I’m able to maintain colors fairly good and even whites are not to far off.

I just finished watching a rather dark chapter from the movie King Kong and although the light level was not that of midday sun outside it was almost that bright and the images maintained a good contrast ratio.

Below are the screen shots. Please keep in mind the extreme ambient light levels when critiquing them.

I do have some pictures of the screen under room lights with projector off if anyone would like to see them, or details on how you can construct a similar screen.

Click thumbnail for full size image.....

http://thumb2.webshots.net/t/59/59/1/80/24/2233180240068493142kzcstF_th.jpg (http://entertainment.webshots.com/photo/2233180240068493142kzcstF)

http://thumb2.webshots.net/t/57/557/5/3/83/2230503830068493142lOYbPJ_th.jpg (http://entertainment.webshots.com/photo/2230503830068493142lOYbPJ)

http://thumb2.webshots.net/t/14/14/8/54/64/2586854640068493142hyhIEb_th.jpg (http://entertainment.webshots.com/photo/2586854640068493142hyhIEb)

http://thumb2.webshots.net/t/53/653/8/57/23/2621857230068493142dtiIkq_th.jpg (http://entertainment.webshots.com/photo/2621857230068493142dtiIkq)

http://thumb2.webshots.net/t/59/459/0/15/28/2980015280068493142vdrsWW_th.jpg (http://entertainment.webshots.com/photo/2980015280068493142vdrsWW)

http://thumb2.webshots.net/t/57/657/5/83/6/2175583060068493142nVEJEM_th.jpg (http://entertainment.webshots.com/photo/2175583060068493142nVEJEM)

http://thumb2.webshots.net/t/22/23/5/91/50/2556591500068493142sgoDiL_th.jpg (http://entertainment.webshots.com/photo/2556591500068493142sgoDiL)

[BoomerBrian]

Looks pretty good to me. So, are you going the spill the beans? :D

[mynym]

Looks nice man.

[bud16415]

Thanks guys it’s really pretty amazing sitting here watching this screen with so much light on. I’m guessing it’s at least as bright as my computer monitor maybe brighter. And the room lights seem to have almost no effect on the image. When I shut them all off a while ago. It didn’t seem to change the picture too much. It gets about maybe 5% to 10% brighter than what you see in the photos.

BoomerBrian
I’ll post some more pictures tomorrow after all the light bending alchemists have a chance to weigh in.

I have had a few PM’s wanting more info also.

[BoomerBrian]

OK. I will wait. I do have a few questions.

1) Is this a DIY application or something you are going to sell?

2) In the pictures it appears there is no ambient light reflecting off the screen. So you are saying the lights are on and the black border around the picture is from the projector? If so, that is awesome.

3) Trick or Treat!

[MississippiMan]

Ok Bud,

Boomer made a very good observation. 'Cmon now, show us a shot of the screen from a distance, with all the boarder showing out to the edge and the wall's illuminated surface beyond.

Ya said ya got 'em, so post 'em

You Jolly Jokester, you. :p

[mn3kgtvr4]

Brilliant. Of course, I fall into the scientific camp so will need to see at least your screen compared to a matte white surface in the same frame. Perhaps screwing the light bulbs all the way into their sockets next time you turn them on will offer a better reference as well, jk.

[MississippiMan]

Perhaps screwing the light bulbs all the way into their sockets next time you turn them on will offer a better reference as well, jk.

:p :p :p :p :p :p :p :p :p :p :

[bud16415]

That’s a good one about the light bulbs. But I can tell you they were all screwed in and fully powered throwing lots of light. I didn’t think to put a 1.0 gain white sample in the picture for reference, but I should have guessed you guys would want to see that in the picture seeing as how that’s something I always ask for in screen shots. I’m at work now so to do that comparison I’ll have to wait until tonight.

I have had quite a few PM’s and I have replied to them with a few clues so I might as well clue the other 200 that have read the post likewise.

First off the screen solution is a simple one layer solution that doesn’t involve the addition of any poly. The skill level in applying it on a scale of one to ten is about a one. It can be copied easily by anyone with items off the shelf from Michel’s

Everything I posted above is the full truth and the black boarders you see in the above thumbnails are being projected by my DLP against the exact same screen surface you see the images on and are at the same time being illuminated by the 500 plus watts of lights I had turned on.

I cant say the cam caught exactly what my eyes saw but I would guess the margin of error between what my eyes see and the screen shots to be less than 5 or 10%.

Oh ya it’s not April first so you are safe there. And it’s purely by luck today is trick or treat. No trick or treat here.

I’ll try and get the other pictures posted sometime today MM. But you of all members here I thought would understand my desire to dangle the carrot a little first. This along with me showing a new scientific approach to screen building, I’m trying to put some fun back in DIY.

Keep the guesses coming…. I’ll see if I can find where I put them other dang photos now….. :D :D :D

[bud16415]

OK. I will wait. I do have a few questions.

1) Is this a DIY application or something you are going to sell?

2) In the pictures it appears there is no ambient light reflecting off the screen. So you are saying the lights are on and the black border around the picture is from the projector? If so, that is awesome.

3) Trick or Treat!


BoomerBrian

I missed your questions when I made my last post. So I’ll answer now.

First off I will not sell or market this idea in anyway. Anyone that wants to use it is more than welcome.

The way the screen works is even though there is a lot of ambient in the room the black you see in the borders is because the screen material is sucking that ambient light up and not reflecting it back as it does the projected light.

And once again not a trick or treat. :D :D :D

[MississippiMan]

Bud,

That's wonderful news actually. Mush better news to wake up to than a well intentioned spoof. I was having a little sport, but not at your expense.

I both can & do appreciate what you have done, and how you "dangled" the carrot. It makes for some anxious speculation for those who have considered other solutions, but found them too challenging or too expenseive.

If it's as good as your (irrelevent ;) ) screenies indicate, your going to have to look forward to 'iconic' status on this board. Ya might not desire such, your even want it in the least, but it's a'knockin', Bud.

I bet all your own "Buds" at the bar are gonna be mytee prowd of ya!

Now, if only the application will work well with lower lumen PJs?

BTW, I noticed that all your photos taken of the X10 show similar lack of sharp resolution that some of my initial ones did. I know of a fact that the shots I took did not accurately represent what I saw in person...the opposite of what I have been accustomed to, and more in keeping with what many others experience. There must be a reason, but I as of yet have not figured it out.

That then is another reason I was not overly anxious about post them, I preferred to wait until the screen cured a bit, I just didn't anticapate waiting so long.

And your 1/2 wrong anyway it seems. ;) Ya mightin' not be a trikin', but yer certinlee a "Treatin' "

[bud16415]

MM

I don’t plan on having iconic status placed on me due to this thread, but it may be a thread that some will remember for a while to come.

You are correct in your assumption that many projectors may be under powered to get the results I’m seeing on my screen.

You are also correct that the images have a soft focus to them, as I have seen in the ones you mentioned of yours also from time to time.
The new digital cams do a good job of focusing by using some hard feature on the intended subject to focus on. One of the draw backs of these modern surfaces we are producing is lack of any detail to focus on. Almost like taking a picture of fog or something. I do believe I know the reason mine are slightly off and I think I have a way to photograph them again and get a sharper image. Unlike BFLF I’m pretty sure my image is coming off just the very outer most surface of the screen.

And I guess you are right there is a element of “Treatin” to this thread. :D :D :D

[wbassett]

...
First off the screen solution is a simple one layer solution that doesn’t involve the addition of any poly. The skill level in applying it on a scale of one to ten is about a one. It can be copied easily by anyone with items off the shelf from Michel’s
.
I'm not doubting that you are telling the truth, why the shroud of mystery though with all the screen shots, promises of more, but no mention as to how it was done?

Bud you've been on here long enough to know that alone is going to set off a debate, naysayers, and yes mudslinging so I don't understand what's going on here. I'm speculating a few things though.

I'm not being a slinger of the mud, but I do know a lot of people are questioning what is going on right now and what the reasoning is. I'm sure you have a reason for not posting how the screen was made, and perhaps if that was said in the first thread it would have explained things to everyone. Right now I really don't know what to say or think...

[bud16415]

I'm not doubting that you are telling the truth, why the shroud of mystery though with all the screen shots, promises of more, but no mention as to how it was done?

Bud you've been on here long enough to know that alone is going to set off a debate, naysayers, and yes mudslinging so I don't understand what's going on here. I'm speculating a few things though.

I'm not being a slinger of the mud, but I do know a lot of people are questioning what is going on right now and what the reasoning is. I'm sure you have a reason for not posting how the screen was made, and perhaps if that was said in the first thread it would have explained things to everyone. Right now I really don't know what to say or think...

Wbassett

Trust me when I say this thread is truthful and intended to be educational. It’s purely by accident it comes at a time when so many people are loosing track of the real meaning and fun of DIY here. Don’t read any subliminal messages into anything ok.

Those that have known me for anytime here know I have no ax to grind and have always tried to be a stabilizing force here.

If you want to think of my opening post in a different light then think of it as a puzzle to be solved if you are so inclined to think about things like that. We all learn by letting our minds go outside the box from time to time. That’s what I did and that’s what I’m posting about.

This is not a reality TV show called “DIY Survivor” where we vote someone off the island each week. Rather we should be opening it up to all and let our minds expand in whatever direction they want to take.

On a similar note I’m really surprised at how many PM’s I have got from new posters and very low posters, some even asking for additional clues. :D

[biglyle]

Just like threads of the past, I must ask "why not disclose the mix upfront?"

I see no need for all the games, and hype building that occurs on this forum.

Post a mix others can make and judge for themselves. That imo is the easiest way to test a mixes value.

[rabbi7]

aluminum foil screen :) what do i win??? j/k

[bud16415]

I think I know how Orson Wells must have felt the day after they broadcast the “War of the worlds” show across New Jersey. And his was purely fiction. :confused:

If you are dragging your DIY screen out into the back yard to set it ablaze hold off OK! :)
Don’t blow away all your data files from your pc just yet OK! :)

I think one of the above posters is right, iconic status is more than a guy can handle. :o

I have started maybe 4 threads during the year I have been here, and I thought I had established myself as a friend to the group and from my past posts and helpful nature this wouldn’t be seen as a “conspiracy theory”.

I’m sorry if anyone ran for the hills, gun in hand to kill any of them aliens. :D

[bud16415]

aluminum foil screen :) what do i win??? j/k


Rabbi7

Nice try but no cigar.

I haven’t thought about a prize yet. Maybe that’s what is needed everyone loves prizes.

How about I package my prototype screen and send it to the winner! I’ll even autograph it. How’s that for a prize?

By the way the aluminum foil screen I made looked really horrible. :D

[rfisher1968]

I would like to see some screen shots with sunlight hitting the screen. I have made a screen that measures 3.0 gain and looks mostly the same with the lights off and on, but sunlight is a different story. It still looks good with all the sun, but its really the killer when your talking about a ambient light screen.

[bud16415]

I would like to see some screen shots with sunlight hitting the screen. I have made a screen that measures 3.0 gain and looks mostly the same with the lights off and on, but sunlight is a different story. It still looks good with all the sun, but its really the killer when your talking about a ambient light screen.


I haven’t measured the gain on this screen but I’m 100% positive it’s much, much lower than a 3.0 gain. :)

My projector is ceiling mounted in the basement, total light control room so the best I can do now is lots of incandescent lights.

And I do agree sunlight is the big killer of an image. I have posted many times about how we perceive brightness of light with our eyes, and how easy it is to fool ourselves by comparing intensity of light we see without taking into account that our eyes have variable apertures. It’s not that sunlight is some different type of light as much as we could be seeing what we view as twice the brightness of light when going from indoors to outdoors and in reality it could be 50 times as bright. That’s our eyes doing what they were intended to do. Trying to make us see a constant brightness as best they can.

[biglyle]

Bud, I still fail to see why you need to post all this cryptic stuff, just post the mix and pertinant info regarding it. Why are all the games nessasary?

I mean this with no disrespect what so ever. It just seems very tiresome to play these games.

[MississippiMan]

What's tiresome is all the pressue he's getting. And it always comes with declarations of "I'm not trying to be....."

.....and unfortunately, all the same gnats are now swarming. Bud doesn't deserve any of the pressure, accusations, or any doubts about his sincerity. If he chooses to present his find in a whimsical or coy manner, as long as he states that it WILL BE DONE, in his own good time, and be totally open source for the benefit of all DIY'ers, adverse or abusive responses or implied accusations to the contrary should be reported by any/all people who find such actions offensive.

he said the info would be forthcoming. There was no inkling of such a developement 2 days ago and everyone got along just fine (...so to speak...) Why the rush to pre judge his motives or force immediate disclosure?

Leave him be, or just leave it alone, but don't pressure him anymore than a gentle nudge.

I'm betting you haven't bothered to send him a courteous PM to "get on the list", as he suggested others could do/have done. That would be just to decent.

[rabbi7]

how 'bout some more clues... is there actually painting involved, or is it all based on screen material?

[bud16415]

Bud, I still fail to see why you need to post all this cryptic stuff, just post the mix and pertinant info regarding it. Why are all the games nessasary?

I mean this with no disrespect what so ever. It just seems very tiresome to play these games.

I’m guessing biglyle didn’t like the movie “The Da Vinci Code” very much.

But I guess you are right no one reading this really wants to think about ambient light rejection and try and figure out the pictures I offered last night and in doing so gain insight into concepts surrounding bad light rejection while allowing good light to return to the viewer.

Until I tried making this screen for myself I had no idea if this idea would work or not.

But part of the reason I posted it in this fashion was because I have posted this very same thought at least 10 times in other threads on the topic of ambient rejection and all but a few even paid slight attention. I have seen hundreds of threads started asking the same basic questions over and over. I thought why not start a thread about a single concept. And to gain a little interest in that concept for the sake of discussion and to do so show some results but let the viewers think about the idea a little before they know what it is.

But I guess no one is interested in that approach.

One thing I don’t remember saying this was a mix???? :D :D :D

[MississippiMan]

how 'bout some more clues... is there actually painting involved, or is it all based on screen material?

Now there's a good suggestion, made with nothing but courtesy and respect.

keep 'em coming, and the feeling of goodwill generated by such genteel prodding will elect a more certain response than posts that only make :( appear.

[MississippiMan]

I thought why not start a thread about a single concept. And to gain a little interest in that concept for the sake of discussion and to do so show some results but let the viewers think about the idea a little before they know what it is.

But I guess no one is interested in that approach.

One thing I don’t remember saying this was a mix???? :D :D :D

I'm interested. ;)

....but I gotta go to work. :mad:

[BlackCatt]

ok... so far we have...

1) items off the shelf from Michel’s
2) its not a mix
3) Bud, has discussed the screen material / technique in other threads on several occasions

[Highside]

OK,

I'll take a generic bite. As I'm typing this you gave a clue that may be in the same direction as my thinking. :rolleyes:

You have a very bright projector. :eek:
You stated that LL PJs may not be able to get the same results. :(
1 on a scale of 1 to 10 :D
"fuzzy" photographs........... :(

and just for the fun of it, like guessing how many jelly beans are in the jar............ ;)

You are projection onto felt or microfiber, but I cant guess the color...... :p :p :p

Rob

[bud16415]

how 'bout some more clues... is there actually painting involved, or is it all based on screen material?


Just my luck

The only one that got the intent of the thread was a Rabbi and a MississippiMan.

That reminds me of a joke a Cajun and a Rabbi go into a bar…. Ok it’s my thread and I’m getting off topic. :D

No paint involved…. But it could have been just as easily been paint. One can 3 coats would have done it.

[biglyle]

Ahhh, Maurice, the most guilty non-topic babbler of all.

C'mon, the only reason you are on this thread is because it has the possibility of this affecting your bottom line.

[MississippiMan]

I'll let Bud deal with you off topic content.

[biglyle]

Bud,

I am not sure how this will create disscusion on ambient light rejection, but it is your thread, so knock yourself out.

What I am saying to be more clear is that presenting your findings will allow others to try it, see if it works as well as you say, and then discuss it, knowing then what the hell it exactly is they are discussing. It will also work to prevent repeats of situations that occured in the past.

Again, no anomosity at all, and that the truth regardless of what mr snake oil says.

[bud16415]

OK,

I'll take a generic bite. As I'm typing this you gave a clue that may be in the same direction as my thinking. :rolleyes:

You have a very bright projector. :eek:
You stated that LL PJs may not be able to get the same results. :(
1 on a scale of 1 to 10 :D
"fuzzy" photographs........... :(

and just for the fun of it, like guessing how many jelly beans are in the jar............ ;)

You are projection onto felt or microfiber, but I cant guess the color...... :p :p :p

Rob

Hate to see you leave MM the west coast is just waking up. Another 10 million inquiring minds awake and reading.

No felt and no micro fiber….

And I knew that Da Vinci Code clue would draw in the big guns.

No jelly beans were hurt in the making of this screen.

[jaydonoghue]

OK, I'll bite. How big is the screen? And how far away is the PJ?

This thread is funny. :)

[bud16415]

OK, I'll bite. How big is the screen? And how far away is the PJ?

This thread is funny. :)

Jaydonoghue

Where in the heck did you come from? What makes a guy think he can come in here with 6 posts under his belt and a shiny green shamrock icon as an avatar and think he can ask thought provoking questions like that.

Ok you asked and if I don’t answer I’ll get beat up by the masses. In fact I’ll give a little more info than you ask for.

The throw distance was 36” and the on screen foot lamberts were around 500 to1000FL :eek: :eek: :eek:

[mn3kgtvr4]

Hmm, Michael's but no paint. They don't sell fabric to my knowledge. That's Joann's. Funny how DIY screens make manly men into knowledgeable shoppers of those stores.
They do sell various foam boards and things like that likely in multiple colors.
Something like that might make it easy to suck light really well, but what about the PQ?

[mn3kgtvr4]

oh

[wbassett]

Some of the hints are this is
"a simple one layer solution that doesn’t involve the addition of any poly"...

it came from Michael's...

"How about I package my prototype screen and send it to the winner!"-- meaning it's NOT a substrate or anything large and bulky that can't easily be mailed (Bud uses canvas a lot and paints on canvas)...

"the screen material is sucking that ambient light up " and "Unlike BFLF I’m pretty sure my image is coming off just the very outer most surface of the screen." and "One thing I don’t remember saying this was a mix????" -- so we're most likely looking at some sort of material here-- can't say 100% though...

Bud...any of these observations right or close?

[bud16415]

Some of the hints are this is
"a simple one layer solution that doesn’t involve the addition of any poly"...

it came from Michael's...

"How about I package my prototype screen and send it to the winner!"-- meaning it's NOT a substrate or anything large and bulky that can't easily be mailed (Bud uses canvas a lot and paints on canvas)...

"the screen material is sucking that ambient light up " and "Unlike BFLF I’m pretty sure my image is coming off just the very outer most surface of the screen." and "One thing I don’t remember saying this was a mix????" -- so we're most likely looking at some sort of material here-- can't say 100% though...

Bud...any of these observations right or close?

Yep they all are…. :D

[wbassett]

Hmm, Michael's but no paint. They don't sell fabric to my knowledge. That's Joann's. Funny how DIY screens make manly men into knowledgeable shoppers of those stores.
They do sell various foam boards and things like that likely in multiple colors.
Something like that might make it easy to suck light really well, but what about the PQ?
The do sell artist supplies and picture frames, matting material and things like that ;)

[biglyle]

The PJ is only 36 inches from the screen?

If that is correct, then the image would need to be magnified to be a good size, or is only 2 feet wide or the PJ is actually behind the screen, as some PJs allow. (even though I have no idea how that would would)

[biglyle]

I am guessing the image is bright as your monitor simply because the image is the size of your monitor.

[mn3kgtvr4]

Prediction:

The newest trend in the DIY screen area will be "Nano-Screens" with everyone going towards smaller and smaller screens with projectors mounted closer and closer to the screen. Within a year this forum will die and we'll all take over the Direct Tube Display forum trying to find the holy grail of a 5" black tube, flat screen 1080P CRT tv available from Wal Mart below $150 that we can apply a duster coat of matte grey finish to to further reduce ambient rejection. Some will argue it's possible. Some will argue to keep the screen factory fresh and just view it under their bed covers at night for total light rejection.

[bud16415]

I am guessing the image is bright as your monitor simply because the image is the size of your monitor.


Be careful biglyle you are coming dangerously close to enjoying this. :D :D :D

[rabbi7]

hmm.. not paint, but could have been paint..so maybe not so much the screen itself. maybe something surrounding/covering the frame to contain the light? seems like you do like canvas if i remember tho...

not really a Rabbi :) just a nick I picked-up 'fore I gradjiated frum colledge

Brian

[wbassett]

No felt and no micro fiber….

And I knew that Da Vinci Code clue would draw in the big guns.

No jelly beans were hurt in the making of this screen.
Da Vinci was an artist and scientist... I'm still thinking along the lines of what exactly is located in the back corner of the store (at least all the Michael's I have been in all the artists supplies were in the back of the store to the right...) now what all is back there???

And we also know this is small... will you entertain a question? Can this be obtained in larger sizes?

[ilsiu]

The throw distance was 36” and the on screen foot lamberts were around 500 to1000FL

Using the Projectorcentral.com calculator, for a 36" throw the image diagonal ranges from 23" - 26".

[roar]

Can we get a confirmation on a screen size? projectorcentrak says your projector does a 23" diag with a 36" throw... true?

Edit: That will teach me to walk away and not click submit :) Same thought!

[bud16415]

Can we get a confirmation on a screen size? projectorcentrak says your projector does a 23" diag with a 36" throw... true?

Edit: That will teach me to walk away and not click submit :) Same thought!


Yep the screen was about 26”

[rabbi7]

OK, so we know this is small, not inherent to the material used (canvas maybe, no paint vs. 3 coats of paint, but not a mix), and is only one layer, and he's using a bright PJ, so i'm guessing it has to do with containing/concentrating the light source maybe?

[biglyle]

A bright PJ, witha 36 inch throw to a 26 inch size screen is no breakthrough. You could pretty much use a cement wall and get excellent results. C'mon bud, there is obviosly more to this, because everyone already knew that lots lumens, plus small screen and short throw is a light buster.

So whats the real point here?

[MI_CT]

"First let me explain the lighting conditions in my room for these shots. All room lights were on that’s a total of (8) 60 watt ceiling flood lights the closest 2 being 4 foot from the screen. in addition I added (2) 100 watt bare bulbs each side of the screen about 3 feet in front of the screen and 2 feet to the sides. The ceiling is a gloss white pegboard material. "

My first quess would be how the lights are arranged around the screen. Im not even going to pretend to explain any kinds of science involved with the lights. But don't think Bud would have explained the lighting conditions to this extent if they didn't effect the picture.

As for screen material, I don't know maybe he found a color or some material that absorbs just the wave length we perceive from abient lighting?

Well let me know if im even close lol.

MI

[TheLidlessEye]

Yep the screen was about 26”

Congratulations! You've re-invented the $100 direct view CRT!

[biglyle]

Congratulations! You've re-invented the $100 direct view CRT!


Yep, and it only sets you back $2500

[bud16415]

I just got this PM so its time
(come on man !

spill the beans !

I got three gray hairs just from this morning .)




At 11:58 EST on 10-31-06 member extracheese aka Ken PMed me with the correct answer. So I have to declare him the official winner.

Below is a thumbnail of the setup I used. It’s taken facing the projector but the screen side is the same flat black craft paper as on the back side. The reason I moved the screen so close to the projector was to demonstrate the neutral gray concept to its maximum potential. Neutral grays run between white and black. The point I was making with this experiment is to show that the percentage of black added to white does not limit the screens ability to accurately reproduce the whole spectrum of colors. As the screen shots show white can be projected from black given enough lumens. I didn’t have a 50,000 lumen projector handy so the logical step to use for experimenting is moving the screen closer to the projector.
And yes the out of focus image is caused by the projectors limits on short focus. Given an add on lens the image would have shown very sharp. The other mode of the experiment was to show the ratio of good lumens to bad and how that effects ambient light.
IMO We will always be looking at a ratio of this type. There are a few simple straight forward things we have learned on this forum to date. We have learned how to improve gain at the cost of viewing cone. We have learned that screens can have improved efficiency while appearing darker to improve our perceptions of contrast. And I hope we have learned that the percent of gray in of itself does not crush whites to grays and alter colors. And darker screens with extra lumens tips the balance in favor of ambient “rejection” not really the correct term a better term would be ambient competition.

I know this example is not the answer to your dream screen to be used in your back yard on a sunny day, rather the point I wanted to show is that it is possible.

The gain of my little screen would be something like .01 or 100 times the light striking it as coming off. That’s a waste of a lot of power in order to view in bright lights and I don’t suggest anyone do that.

I do hope this helps people visualize this concept that black is just the darkest shade of white.

Thumbnail below:

http://thumb2.webshots.net/t/34/34/5/63/26/2823563260068493142LuqbHk_th.jpg (http://home-and-garden.webshots.com/photo/2823563260068493142LuqbHk)

[klouseau]

Bud, did you use Strathmore Ridge Sheet paper?

http://www.michaels.com/art/online/displayProductPage?productNum=fa0284&channelid=

These raised ridge papers are excellent for decorative applications and backgrounds. Acid-free, 80 lb. cover colored art sheet. 20-inch x 26-inch

[skyman00]

Wheww! Good thing Klouseau is on the case! -j

[bud16415]

Bud, did you use Strathmore Ridge Sheet paper?

http://www.michaels.com/art/online/displayProductPage?productNum=fa0284&channelid=

These raised ridge papers are excellent for decorative applications and backgrounds. Acid-free, 80 lb. cover colored art sheet. 20-inch x 26-inch


The actual paper I used was a couple sheets I had left over at work. And the exact spec I can’t tell you for sure what it was. One side is shiny and the other a little dull. I put one on each side of the cardboard I hung up in the photo so what you are seeing is the shiny one. The flatter dull black side was what I projected to. It actual look about like what flat black stage paint looks like.

The point I was making is I don’t think anyone wants to make a pure black screen at this point. But I wanted to push my experimentation to the edge.

There are a lot of people of the mind set that shining white light at any color returns a light of that color. So the logic goes if you shine white light at dark gray you see brighter dark gray.

There is a lot of belief that projecting to black causes colors to shift to blue. The addition of a very small amount of black is said to make whites blue and skin tones muddy. I don’t totally understand those concepts yet and don’t claim to be more than a novice at this. That’s in part why I do these experiments to explain things to myself. And in the process there are 100s if not 1000s of others out there going, “I was wondering the same thing.”

Its easy to stand on the sidelines and say everyone knows that. Or “Wow Bud you made a $2500 26 inch TV.” But it’s in trying something, anything and then viewing and discussing the results that someone will be sparked by the idea to try something else.

I think the people that participated in this thread enjoyed the time spent. After all these threads are a lot like TV channels no one makes you stay and view one or post to them.

In the end I wish all members here that post regularly do a search on their own name. It will list all your posts in order. Read thru them and take stock of when you helped someone with a answer and when you put forth something that informed the group as a whole.

I hope my little thread didn’t cut into anyone’s day to much. It did make 2 pages faster than any I have seen in a while. :D

[TorAtle]

Here is my super special paint. Hope you like it :)
http://avforum.no/forum/attachments/av-rom-konstruksjon-optimalisering/13446d1161543669-tor-lager-tv-aut_0219.jpg

[movielvr2006]

i believe Bud has demonstrated a few points:


people get pretty crazy when someone posts something controversial. everyone needs to settle down in that respect. have some fun!
people aren't always asking the right questions when they analyze or give advice, screen size should have been the first question asked.
a dark screen may be the perfect fit for some situations.
Bud has a good sense of humor, perhaps a bit twisted, but good :).
Bud may deny it, but he has tricked us on the fine Halloween Day! :p


now to continue with item 3, i have been using this very concept for about 2 months now. I have a neutral gray screen with gain in the area of 0.47 to 0.50. However I only run a 55"-60" screen with about 500 available lumens. Whites are not crushed, black levels are of course excellent. My screen is a painted screen using flat latex only. that's it, simple. just taking advantage of the simplicity of the science and i'm happy with what i have for now.

i'll admit however, this is not the solution for someone who doesn't have a high output projector, or who wants a large screen.

oh, and Bud, i'm glad you all let us have some fun today. good job.

[bud16415]

i believe Bud has demonstrated a few points:


people get pretty crazy when someone posts something controversial. everyone needs to settle down in that respect. have some fun!
people aren't always asking the right questions when they analyze or give advice, screen size should have been the first question asked.
a dark screen may be the perfect fit for some situations.
Bud has a good sense of humor, perhaps a bit twisted, but good :).
Bud may deny it, but he has tricked us on the fine Halloween Day! :p


now to continue with item 3, i have been using this very concept for about 2 months now. I have a neutral gray screen with gain in the area of 0.47 to 0.50. However I only run a 55"-60" screen with about 500 available lumens. Whites are not crushed, black levels are of course excellent. My screen is a painted screen using flat latex only. that's it, simple. just taking advantage of the simplicity of the science and i'm happy with what i have for now.

i'll admit however, this is not the solution for someone who doesn't have a high output projector, or who wants a large screen.

oh, and Bud, i'm glad you all let us have some fun today. good job.


Well maybe there was a 10% effort at having a Trick or Treat.

And perhaps as the thread evolved maybe another 10% psychologically experiment.

I do want to wish everyone a Happy Halloween and be careful with the little ones running about tonight when driving. :)

As to item 4 on your list “I resemble that remark.” :D

I do have to give Movielvr2006 some credit for me trying this. Something he posted in a thread the other day got me thinking. :)

If I needed a projector for a high ambient light environment and say I bought 3 Sharp XR10X projectors at $800 per I would have $2400 invested in a system that could put out 6000 lumens. And I’m willing to bet I could fill a 150 inch screen that has been grayed down to a very ambient tolerant level. Something like a .4 gain dark neutral gray.

It would be interesting to see how such a setup would compare with a $2400 high CR projector on the best high gain ambient screen.
But that’s the topic for another thread. And I’ll let someone else try that. ;)

[Highside]

I knew I was close. :p

Had I read into your posts a little better, I.E. realized that you said Michael's and not JoAnn's, I would have guessed a different material. :eek: But same concept though..... ;)

I think I need to stay away from JoAnn's for a while and decompress... :D :D

Rob

[rabbi7]

I enjoyed the puzzle, bud :)

[<^..^>Smokey Joe]

:D

Nice demonstration.

So one could conclude that if you have a perfectly neutral surface as a shade of grey, even neutral black, when the ratio of lumens gets high enough above the absorbsion value(with black generally being between 10~20% reflectivity) we would see a bright picture without color distortion because the reflected colors are coming off a neutral.

I suspect though, because it is very hard to get absolutely neutral, as some have already proved there is a color shift towards the offending color. The higher the lumens ratio though the less the noticeable effect, until the neutral becomes a color. But the color shift will always be there by the same amount as the color is off the central balance.

There must be a shift of contrast ratio though, otherwise you would not see better blacks. If it didn't grey or dark screens wouldn't work at all.
The question is, how far can one go. I suspect we could place a lux value on this so each person could measure and have some values to work with as a starting point.

That is, given lux value at the screen surface(direct from PJ)( which contains any ambient light lux) + shade of grey and reflectiveness of the screen surface = reflective lux - ambient light lux.

Something like that anyway.

It will all depend on lux ratio's.

I'm going to attempt to prove some of this to myself with a DIY HCFR colormeter I'm in the process of building.

[biglyle]

Now try and figure out how many lumens you would need for this to work with a 100 inch screen and a 12 foot throw?

This just doesnt appear to be doable in a real world environment, not now or in the near future.

[movielvr2006]

Now try and figure out how many lumens you would need for this to work with a 100 inch screen and a 12 foot throw?

This just doesnt appear to be doable in a real world environment, not now or in the near future.

about 2500 lumens assuming the following:

a very dark gray screen with gain around 0.25 to 0.28
16:9 screen at 100" diagonal
a matte surface with 180 deg viewing cone, no metallics needed

[prof55]

A Christie 20K will do 500fL on an 87" diagonal 16:9 screen, so this would be an excellent choice for your new creation.

Use it without a screen, and the neighbors may be able to watch the show in reverse on your siding. :D

Better yet, try a 50" screen with a 3 foot throw - 1500fL! Might have a burn-in problem on the wall, though.

Garry

[Lindahl]

Thanks for wasting 10 minutes of my life. Where do I send the bill, Bud? Not all of us have time to waste on silly games.

[wbassett]

At least it was only 10 minutes Lindahl... some threads that promise actual mixes or methods drone on for weeks like this and in the end nothing anyway! So 10 minutes wasn't too bad...

I think the whole reason behind this was Bud was trying to make a point and not say black construction paper is the way to go ;)

[mn3kgtvr4]

Pretty entertaining, Bud. I've gone pretty dark gray, but wouldn't have expected total black to give any whites. Good and worthy experiment that logic would not have compelled me to try.
Since I started experimenting with mica flakes a few years ago I've found I can go much darker in the gray for ambient light absorption while letting the mica flakes help boost the light - from a normal pj distance and screen size. Would have never guessed whites would even appear close to white with a black surface. Pretty cool.

[prof55]

If you shine enough light at anything short of a black hole, it will return "white". It's just a matter of having enough light left after absorption.

[wbassett]

If you shine enough light at anything short of a black hole, it will return "white". It's just a matter of having enough light left after absorption.
So Prof this may not be too dark then?
http://i96.photobucket.com/albums/l190/wbassett/Munsell_N8.jpg

What kind of lumen output would you say for a shade this dark? 2000 lumens? Any guesses as to the lower limit of CR as well?

Reason I ask is I am getting a gallon of this very soon to play with :)

[prof55]

At 202/202/202, that's not really very dark, Bill.

High Contrast Cinema Vision measures 201/196/205, and 11/48 lampblack in 1qt UPW is 201/198/213.

[wbassett]

I didn't think it was either, but it seems to be to a lot of people.

Sorry Bud didn't mean to hi-jack your thread!

[bud16415]

Highside
Thanks for sitting in and enjoying the challenge. You wouldn’t believe the stores I have been in that I thought I would never hang out in. but if when you walk in JoAnn’s and they look up and go “Hey Highside” it might be time to give it a rest.

Rabbi7
Thanks for the input. And I don’t think I want to know where the nickname came from in college.

Smokey Joe
Thanks for the input. I think you are exactly on track. And you are right pure neutral anything is hard to get too. Lucky thing for us all these projectors come with some calibration. So in terms of neutral there is always going to be a plus or minus. But we do have to get in the ball park.
No one needs 180 degree viewing cone that’s why in my case I did the sheen study and gained a little of the light back I lost with the addition of black on my current screen. The other proven method to date is the addition of metallic. And or a combination of both. The unplowed ground for me still is texture and its effect on all this.
If I do a texture experiment I’ll remember to not be so dramatic.
Keep us posted as I know you will with whatever direction your mind takes you. Remember this is fun, that’s why we do it.

Biglyle
What can I say.
I’m going to relate a true story. I graduated high school in 1972 and that year I used to play chess against my calculus teacher every day in study hall. One day I mentioned to him after seeing a demonstration at PSU where they had something called a computer. They feed a deck of IBM cards into this machine a stack about 6 inches high and the computer was able to play tic-tac-toe against you by printing out a new sheet of paper for each move you made. I told this teacher after seeing this that someday I think a computer will play chess against a human. I then got a 30 minute oration on how that could never happen and how ridicules I was to even think such a silly thing. He said my God it would have to do well over a million calculations to make a single move.
I’m glad I didn’t mention someday they might make projectors that bounce light off millions of microscopic mirrors timed just right with a color wheel to produce a trillion colors on a screen.
The near future is so close to the way out future these days I would never say never.

Movielvr2006
I don’t know about you but I’m going to take a few nights eat popcorn and catch up on some DVD’s
Thanks for the input as always.

Proff55
That’s why we need to start a stainless steel siding company and forget about all these paints.

Lindahl
Nice to meet you also. I haven’t read any of your posts but I’ll try and catch up on them.
I’m assuming the 10 wasted minutes was reading time. By my last calculation I think I have invested several hundred hours reading about who should be allowed to post and who shouldn’t.
But send me a PM with a address or a paypal account and I’ll reimburse you for the 10 minutes.

Wbassett
I hope I didn’t spoil your breakfast this morning.
Keep going with the laminate stuff you are on to some good things there.
Not that I’m into predicting things but if I had to predict something it’s that someone is going to make a killer curved screen out of this stuff. And its going to be the next big I have to have one screen.
This thread is free to hijack anyway you like.

Mn3kgtvr4
I’ll never forget that name…lol…
Good stuff keep with it.

[wbassett]

Didn't spoil my breakfast... wasn't sure if this was a launch into something commercial is all lol ;)

Actually I found that neutral gray really isn't that hard to find, and when I say neutral I mean honest to god neutral! (as far as laminates, I love them, but shhh, I've made more painted screens than laminate screens, and I'm still playing around with both as screens ;) )

[FremontRich]

I would have "thunk" this thread more suited to April Fools Day rather than Halloween... ;)

[ilsiu]

I actually think this thread has a lot of useful information:

- in the presence of ambient light, the darkness of the screen screen dictates the black level

- the brightness of the projector dictates the white level

- if there's enough light, white can be produced on a literally black screen

- 'brightness' (by that I mean FtL) can be increased by reducing screen size

- the final image quality is a series of tradeoffs of all of the above.

These may seem like obvious statements, but they tend to get lost with all the hoopla about latest and greatest paint mixes. Screenshots seem to especially stir up a lot of excitement, as they did in this thread.

For those that are starting from scratch and looking for a projector and screen combination for ambient light conditions, these things are alot easier to control from the beginning than mixing/rolling/spraying an exotic paint mixture, and will take you a long way towards something that will satisfy you.

[FremontRich]

I actually think this thread has a lot of useful information:

- in the presence of ambient light, the darkness of the screen screen dictates the black level

- the brightness of the projector dictates the white level

- if there's enough light, white can be produced on a literally black screen

- 'brightness' (by that I mean FtL) can be increased by reducing screen size

- the final image quality is a series of tradeoffs of all of the above.

These may seem like obvious statements, but they tend to get lost with all the hoopla about latest and greatest paint mixes. Screenshots seem to especially stir up a lot of excitement, as they did in this thread.

For those that are starting from scratch and looking for a projector and screen combination for ambient light conditions, these things are alot easier to control from the beginning than mixing/rolling/spraying an exotic paint mixture, and will take you a long way towards something that will satisfy you.


May be so, but what are the practical applications to what bud16415 showed us? ;)

[bud16415]

FremontRich
Sure I made the thread a bit more fun than it had to be, but please try and understand I did so with the intent to illustrate a item of science that has been discussed before but I don’t think has been widely understood. The proof of that is the questions people asked and what they thought was going on. And it wasn’t just a bunch of first time posters new to projection but was read by a wide cross section of people here. When I first put the thread up the other night I thought by morning I would have a post from movielvr2006 or tiddler or proff55 saying nice try bud it looks like a black screen from 3 feet to me.
When I saw people getting interested (and being interested is learning) I thought let the questions go. I had about 6 PM’s to answer before I ever got my coffee and they all had a positive note and seemed to like quizzing me.
When I do a April fools spoof trust me it will be much more involved…..

There are many practical applications to this and it’s a matter of degree. The thread I started a long time ago is linked in my signature below. It began as a study into neutral gray and what I found worked in my specific case and how others could build on that idea and methodology.
Its been my long standing belief that if a person has any extra lumens in their overall system a very real improvement can be seen by going to the slightest shades of gray. Doing that along with some of the other light boosting ideas is a strong path for people wanting to experiment with this. Its not the only path but its one that IMO still has a lot of work to be done.

That was my real intent of this thread was to build some enthusiasm in some of the new members and let them know it’s ok to experiment and feel free to throw new ideas out on the table. Quite honestly I came here just looking for a paint mix or a place to buy some paint from. And I’m sure there are some that wish I would have bought some GOO and left.
But this is just too much fun to have done that.

Ilsiu
I couldn’t have said it any better.
When I first started my experimentations into DIY I was a strong supporter of neutral gray and utmost simplicity. And that still is a very strong position I hold. But I’m a hard sell and I have found virtues in many other more complex solutions. There are some solutions I’m still out on. And others I’m leaning strongly against. But I believe in keeping a open mind until such time I find a way of convincing myself if something works or not.

[Clarence]

Bud,

You're certainly entitled to have a little fun here and I recognized that something was up when you were so secretive with the details, especially when you were so adamant that your "breakthrough" wasn't a trick.

But I just wanted to dampen the giggles just a little and voice my concern that this DIY Screen section has been in a downward spiral for a while and finding practical information here has become more and more difficult.

The other forums have a tendency to build a larger and larger useful knowledge base as the number of posts increase, but DIY Screens seems to get more and more cluttered by endless over-hyped "breakthroughs" and DIY approaches that somehow must become too good to disclose for free so they evolve into secretive marketing schemes.

I sympathize with anyone who just bought their first projector and comes to this forum seeking a practical, affordable DIY screen. They've got a lot of chaff to sort through. Trying to filter out the hype and unbalanced comparisons is part of the fun for those of us who come here weekly for year after year, but for someone who just pops in, this type of post typifies the clutter that they have to fight against when seeking "details on how you can construct a similar screen"....
...so superior to anything I have seen to date...

I had to take some screen shots and post them for the group to view...

First let me explain the lighting conditions in my room...

The pictures were taken hand held and with cam set to auto...

The screen was larger than the image and the black masking...

The projector is my Sharp XR10X...

I post these photos to show the deep black levels that are possible with this new DIY screen under the most severe ambient conditions...

Notice while keeping these rich dark blacks I’m able to maintain colors fairly good and even whites are not to far off....

Below are the screen shots. Please keep in mind the extreme ambient light levels when critiquing them.

I do have some pictures of the screen under room lights with projector off if anyone would like to see them, or details on how you can construct a similar screen.

[bud16415]

Bud,

You're certainly entitled to have a little fun here and I recognized that something was up when you were so secretive with the details, especially when you were so adamant that your "breakthrough" wasn't a trick.

But I just wanted to dampen the giggles just a little and voice my concern that this DIY Screen section has been in a downward spiral for a while and finding practical information here has become more and more difficult.

The other forums have a tendency to build a larger and larger useful knowledge base as the number of posts increase, but DIY Screens seems to get more and more cluttered by endless over-hyped "breakthroughs" and DIY approaches that somehow must become too good to disclose for free so they evolve into secretive marketing schemes.

I sympathize with anyone who just bought their first projector and comes to this forum seeking a practical, affordable DIY screen. They've got a lot of chaff to sort through. Trying to filter out the hype and unbalanced comparisons is part of the fun for those of us who come here weekly for year after year, but for someone who just pops in, this type of post typifies the clutter that they have to fight against when seeking "details on how you can construct a similar screen"....


Clarence

I agree there are two distinct groups of people that come to this forum.

The “Light Bending Alchemists” as Tiddler coined them.
And the fellow like me that didn’t have a clue surfed in here and was looking for an addy to buy some Goo. But I didn’t know Goo was the name then because my sister saw it on a tv show and forgot the name. So that will give you an idea of my starting point.

I read a lot and posted a little asking questions and doing simple screen experiments. I latched on to a few things that worked out for me and I did something that maybe .001% of the people do that come here. I started 3 threads not all at once. (they are listed in my signature) the first was a thread asking advice and explaining what I learned by following that advice. It dealt with the use of poly. (no grandstanding) the second and third dealt with the screen I built from the knowledge gained here. One being the mechanical aspect of a large framed screen. (a how to thread) and the other the methodology of my screen paint and application) I titled that thread a “a simple screen paint” it was what I came here looking for and my thought was put it out there for someone like me coming here to at least read and maybe save them some steps and time and money. When that thread was started I actually had high hopes some moderator would go “Ya know that would make a great sticky thread” because that’s where newbie’s should be looking first. That’s where I went first. Well that never happened and unlike a lot of thread authors I never felt the need to give it a gentle “bump” every 3 months. I did do one other thing not everyone does and that is I kept a photo essay of humble basement media room and the process I went thru building it on a shoestring. It’s easy to do a photo essay on the 50k home theater with all new construction. It’s a bit more humbling to show off your 1k total effort. That page has had over 80,000 views to date. I have received 100s of PMs asking advice and many wanting to relate how something they read saved them time or gave them a great looking image to watch.

So I do know the confusion people coming here face and have tried to help make this a better place.

As for the items you copied into your post that I first stated. They are and were all true statements. In a court of law we are asked to tell the truth the whole truth and nothing but the truth. Those are 3 totally different things. In my case I did the first and the last. The whole truth was the tease and I think most people got that within the first few posts. You may have not noticed I changed the title of the thread yesterday to (Maybe?) and if you want I can edit the first post to warn newcomers the post may contain more carrot than stick. Or in the interest of cleaning up DIY I can remove the whole thread.

There are several threads I fear a newcomer wandering into actually. The greats thread Tiddler has going about experimentation into RGB paints with all the spectral charts and graphs. I honestly have to say if that would have been in my first days reading here I would have ran for the hills. Also the several dozen threads that always fill the top spaces on the chart that are 10% fact and 90% is someone trying to convince us that someone else is selling a commercial product subliminally to us thru something they write. That element even crept into this thread a few times.

So let me know if you want me to remove the thread. If there is no substance worth keeping in this endeavor I have no problem removing it.

[bud16415]

Opening post edited…

[ninok5]

I will never get back the time i spent reading all 3 pages. :):):)

[<^..^>Smokey Joe]

I wouldn't worry about the time ninok5, time is a construct so we know when something has moved. It's mostly an ilusion.

[prof55]

"Time flies like an arrow, fruit flies like a banana"

Groucho Marx

[gwrieger]

Nothing new with the knowledge of black screen bud. All have been trying to copy the great black screens of the past now for years.

My beliefs still hold true that I think the next "big" DIY thing will be in the use of layered films... one day maybe I will enough time and resources ($) to continue working on this theory.

Take care.

[bud16415]

Nothing new with the knowledge of black screen bud. All have been trying to copy the great black screens of the past now for years.

My beliefs still hold true that I think the next "big" DIY thing will be in the use of layered films... one day maybe I will enough time and resources ($) to continue working on this theory.

Take care.

Gwrieger

I hope no one thinks I’m laying claim to inventing the concept of projecting to a black screen. I personally haven’t seen it done but then again I only view black as a very dark version of a neutral gray. So I guess you could say we have all seen that done.

Everyone is looking for some magic to come out of DIY and IMO and having done a lifetime of creative thinking those magic moments are few and far between.

It’s interesting to note when this thread was an unknown still, how excited people were to unravel it. But once the simplicity was unveiled and it was apparent it was something that would work but did so in a different manner than what was hoped, the discussion stopped for the most part.

I wish gwrieger would tell us more about “the great black screens of the past” I Googled that term and didn’t find a hit. Are these screens something that were made and then never to be recreated again. Is that the “all” that are working on this.

As to films and a break thru in DIY you could be right. It’s too bad you are short on time and cash to pursue these ideas. That’s pretty much my problem also on a lot of things I would like to do.


I did have a little spare time tonight and I took the mini black screen and hung it in front of my full size screen in the way of a test screen. No macro trick or treat this time. I then set my projector on full power and added in the light boost and then maxed the brightness. I was heard to say “I’m givin her all I got captin and I don’t know how long I can hold her together.”

Any guesses on what the image looked like with the XR10X throwing to black from 14 feet this time? Oh and lights out. :confused:
My cam was in the truck or I would have posted pics. I will try and get those shots up before the weekend.

Lets just say I think BigLyle might be a bit surprised. :rolleyes:

[bud16415]

I wouldn't worry about the time ninok5, time is a construct so we know when something has moved. It's mostly an ilusion.


Not too many people know this but time travel into the future has been successfully done. :D

[<^..^>Smokey Joe]

If you aren't shocked by quantum physics you don't understand it.

Light behaves differently when being watched. There are several proofs of this.

We cannot detect light or sound without a medium so we only ever see and hear the world as a reflection.

[FredProgGH]

I never come to the Screen forums, but I'm getting ready to move and when I go I'm getting a new setup with a 720p PJ and a new screen (the current one is a modified pull-down; very lame). Anyhoo- I thought this was a great thread. I have always actually wondered exactly "how dark is too dark?" in a screen; I've always assumed that grey screens must skew the white levels of an image and have stuck to a matte white screen in a VERY dark room. So this was a total eye-opener for me. Extremely fascinating stuff.

[bud16415]

I never come to the Screen forums, but I'm getting ready to move and when I go I'm getting a new setup with a 720p PJ and a new screen (the current one is a modified pull-down; very lame). Anyhoo- I thought this was a great thread. I have always actually wondered exactly "how dark is too dark?" in a screen; I've always assumed that grey screens must skew the white levels of an image and have stuck to a matte white screen in a VERY dark room. So this was a total eye-opener for me. Extremely fascinating stuff.


Fred
Glad you enjoyed it, and also glad you saw the connection.
I actually saw the effect of this long before the light came on for me. It was kind of like going on trust from what others said. The more I got into this idea of a neutral shading of white it became clearer to me. Then when I realized that in most paint mixes the pigments really don’t combine but just sit there side by side as tiny particles in varied proportions. It’s the fact the pigment particles are so small our vision can’t resolve on just a single bit of pigment we then see them as a combined reflectance. On the other hand light striking the surface reflects or is absorbed particle by particle.
Like a mixture of salt and pepper the salt sending back most of the color correctly because it’s white and the pepper absorbing most. That’s in paint.
In the case of my paper screen even though the paper looked pretty black it wasn’t a pure black body. It had some surface sheen and was a very dark shade of gray I’m sure. I didn’t think to measure the surface temperature of the screen before and after projecting but that extra energy was going someplace and my guess is heat.

Fred with the new projector if you have a few lumens left over don’t be afraid to try some of the mixes here now. And don’t be afraid of gray messing the whites up to much. As long as you have enough light you will be ok. And much better IMO than a ND filter for those with extra lumens.

[biglyle]

oh Bud, you should know by now that nothing suprises me around here. ;)

[bud16415]

oh Bud, you should know by now that nothing suprises me around here. ;)

Not much surprises me here ether anymore, but I’m pleasantly surprised you are still reading the thread. :eek: :D :D

[FredProgGH]

I think I may go with either the Optoma H70 if I decide to pinch pennies or the Mits HC3100 if I decide to spend more (and can find one). I'm still trying to weigh options. AFAIK the Mits has lumens to spare but I don't know about the Optoma. I really haven't decided if I feel froggy enough to DIY a screen yet...

And I think you are right about black paper not really being all THAT black, it's just colored black. It would be interesting to project on a slab of onyx or something. Still, the paper is pretty dark and you clearly had great white levels and color saturation. Makes one think- anything could be around the corner with technology. One day black screens and giga-lumen projectors might be commonplace *lol*

[krholmberg]

Bud...

Based on your experiment, have you considered trying a few more sample screens with increasing amounts of black pigment in your "Simple Screen Paint Solution" and a 1:1 poly to water topcoat?

This may become very practical since a lot of people seem to be buying the AX100. It could use the increased black level and has the ability to produce a significant number of lumens.

[bud16415]

Bud...

Based on your experiment, have you considered trying a few more sample screens with increasing amounts of black pigment in your "Simple Screen Paint Solution" and a 1:1 poly to water topcoat?

This may become very practical since a lot of people seem to be buying the AX100. It could use the increased black level and has the ability to produce a significant number of lumens.


Krholmberg

That was pretty much what I wanted people to try with that thread and report back what worked and why.

One of the problems I have or most DIYers have is I just have one projector. Its my belief that suiting the projector to the screen is a big deal. And not just the projector / screen but also screen size and ambient room lighting levels.

That’s partly why I tried the black screen experiment. I thought what can I do at home in my basement testing lab / home theater that could simulate different peoples projectors and conditions. And knowing my projector is of fairly high lumens I thought I could get an assortment of ND filters and by using them I could mock up lower lumen projectors “kind of” I also saw I could move my test screens in and out to get different FL readings under these different light levels. That’s when I thought ok I can get to any FL I need by moving the screen and if I relate them to neutral gray scales and see ambient performance improvement as FL go up how far can I go. Thus the black experiment. Sure that was an extreme example.
But I read a lot of posts where people are using projectors like the AX100 you mentioned shooting to some pretty small screens. Keep in mind each time you half the throw distance the FL go up by 4. so a 60 inch screen is 4 times as bright as a 120 inch screen.

Last week member movielvr2006 commented on how dark a neutral gray he went to with a smaller screen size and a fairly bright projector. And the great black levels he was seeing with some ambient.

So yes its out there if anyone wants to experiment with the idea.

[MississippiMan]

Tiddler's last entry pretty much sums up the most pratical way to get to a point where you have gains without losses.

I'm going to be seeing how a 68" x 38" 16:9 BFLF screen performs with a AX100U today. PJ is at 13' back. Screen is mounted over a Fireplace.

The "hue' will be identical to the screen seen in the "A Friend in need" thread. Same paint actually.

As Bud stated, his experiment was "extreme" and the results wholly dependent on blasting excessive lumens from arm's length onto the black surface. Nothing completely "Black" currently out there can duplicate the same results in 80"+ sizes with nornal levels of PJ illumination coming from over 11" back.

No matter what, other factors and components MUST come into play to be able to begin to reach such levels of pure ambient light watchability. At some point, the use of a "Grey" in darker hues will reach a point of diminshing returns because the darkness of the hue exceeds the PJ's ability to compensate. Even such an application as a dark hued BF is totally dependent on the correct match up of a correspondingly bright PJ. The adjustability of such a mix makes it more readily usable in most any application, but there is still the need to do such adjustment in order to acheive the maximum benefit.

The Panny's 2000 lumens makes the accomplishing of such endeavors more realistic and acheivable, but even so, common sense and practicality must rule.

[bud16415]

Tiddler

Finally …… lol :D

I have been trying to get across for some time just how slight a shade of neutral gray I have been advocating. And how big the results can be. I would put my projector in maybe the top 10% when it comes to brightness and the shade of neutral gray I selected is way down the sliding scale of grays that are talked about here.

Do the comparison as Tiddler mentioned I prefer comparing samples one at a time against a white screen. I used BOC as a base and advocated that in my thread because its something cheep and also something everyone can get their hands on a yard of. That way when we talk or view screen shots we are all on close to the same page.

I actually did my comparison at first with just the small paint cards you get for free at the paint store. I wasn’t looking for overall PQ just areas on a frozen image where white and black came together. The slightest of gray deepened the blacks just as Tiddler said and whites seemed to change very little. There was a point when I could see a slight diminishment in white and that’s where I stopped.

The resulting image was LOTS better than white alone and then the addition of the poly paint blend gave a slight improvement in brightness but gave an overall PQ increase in appearance. The word I want to use is not right there and it’s something you have to see to know if its what you like. Glow, Shimmer, Transparent, Pop…. Pick one

I ended up tailoring my screen to my new projector set on eco mode and brightness at zero with no boosts color 7500k all other settings at zero. I did this knowing throughout the life of the bulb I would need to bump it up from time to time by some means. That’s how I would suggest others approach this also.

Side note: conventional wisdom tells us that lampblack mixes are known to result in a blue push. When calibration showed and I concurred by my own taste that 7500k was right for me based off of skin tones etc. I was once again a little surprised. I would have thought I would have had to go to a warmer 6500k at least.
Still haven’t figured that one out. :confused:

[krholmberg]

Very interesting stuff. I'm interested in making a 112" diag 235:1 screen with Bud's painting technique, but am a bit concerned about the size. If smaller, I probably would get some Do-Able board and see if I like the results. I'd also cut off a bit to the side, paint it with the chosen mix, and then hold it up and see if I like it more. If so, then I'd paint the rest of the board. If not, I'd leave the Do-Able board as is. But, the size I'm looking for is bigger than what is handy to get. 10' x ?' MDF would be workable, but hard to get. I like Bud's canvas a lot, too, but that seems kind of hard to manufacture.

[Thain]

So with a higher lume projector you can have a darker grey screen, right? And therefore have better ambiemt light veiwing while being able to maintain black and white levels , right? I'm more than likely going with a Sharp XR-10x which should be plenty bright.

later

[wamatt]

How does this compare to a DNP Supernova / Screen Innovations Mirage?

[wamatt]

Lol, there is just so much info to read, I cant keep up. Wasnt gonna wade through the whole thread.

[bud16415]

This thread was a joke to prove a point. It is NOT a practical application for a projection screen.

Bud, I really think you should get the administrators to change the thread title to something that is not so misleading.

Tiddler

First off I did change the title on November 1, and also added a lengthy disclaimer not to the end of post 1 but to the beginning of it. I can’t help it if someone only reads the end of a thread and makes some assumptions as to what is going on in the thread. I often read the last entries of posts I haven’t been following but I always take the time to go back to post 1 and try and find out where it all started. And I do at times skip the bulk of the center of a thread if it’s something I’m only slightly interested in.

I did not though start the thread as a “joke” and I didn’t infer that in the amendment to post one. In fact I was trying to demonstrate a real world, true, aspect of projecting to a neutral gray screen, and the fact that the darkness of the gray doesn’t inhibit the reflection of the color white.

I did craft the thread in a method most are unaccustomed to me doing and in doing so I think I drew attention to the thread and also made something a bit boring more fun. That was my goal but many didn’t get it. The fact that some didn’t get it and became emotional within a hour of the first post did illustrate the knee jerk reactions that seem to run rampant only in this forum.

:) (People keep in mind this is FUN!!!) :)

The nice part of it was some people did get the point and at least a dozen have written and said that the thread and the illustrative photos caused a light to come on in their way of contemplating a gray screen, and at the same time enjoyed trying to solve the puzzle.

The ironic thing is this thread raced to 3 pages and surpassed the thread I started laying out the exact same information in my original (simple screen paint) thread.

I do believe from PM’s I have received the thread brought several new minds into the forum that might stick around and contribute.

[bud16415]

Very interesting stuff. I'm interested in making a 112" diag 235:1 screen with Bud's painting technique, but am a bit concerned about the size. If smaller, I probably would get some Do-Able board and see if I like the results. I'd also cut off a bit to the side, paint it with the chosen mix, and then hold it up and see if I like it more. If so, then I'd paint the rest of the board. If not, I'd leave the Do-Able board as is. But, the size I'm looking for is bigger than what is handy to get. 10' x ?' MDF would be workable, but hard to get. I like Bud's canvas a lot, too, but that seems kind of hard to manufacture.

Krholmberg

I’m glad you read thru my other thread and I’m assuming that’s the approach you were talking about following.

Don’t make a 112” pure black screen. ok unless you have a very bright room and a huge light canon.

I do understand the problems associated with trying to make a screen in sizes larger than normal materials come in. that’s what I was faced with and why I started the canvas screen thread. Pretty much finishing a smooth wall and painting it is the other approach and also the large plastic sheets like MM often shows.

The screen I built looks a little harder than it is but I wouldn’t call it simple. My friend just built a variation on it and he didn’t have too much trouble.

I also hope you review all the screen types and screen surface options throughout this forum and make an informed pick based on your room, projector, budget and abilities. Good luck :)

[prof55]

Hey Bud, are you going to bump this thread? :D

[bud16415]

Hey Bud, are you going to bump this thread? :D


Oct 30 2006 was a fun day watching the replies to this OP come in and the subsequent banter.

Prof55
I was going to give it a bump but I read some place today that doing that is self-serving or something. So thanks for doing it for me.

Actually I was hoping the thread would pass into the archives and I could wait a little while for enough new comers to move in that I could start it over again and have all that fun again.

Oh I’m sure I can figure out something new now……. :D

[Lath]

I enjoyed the read...wouldn't consider it "clutter" at all. Thanks, Bud.