RS-MaxxMudd Experiments

Errr..........was there supposed to be pictures associated with the post?? You've been working too hard man. Take a break and enjoy the last couple of weeks left of the short summers we get here in Ontario!

tiddler, you are one driven SOB ... but I appreciate the work you have been putting in here. You are going to save alot of people a lot of time.

GL

I take back all the bad things I ever said about Canadians.

But three day to wait with just one picture a day, you really know how to keep us in suspense.

How would ever thought when they invented the internet we would be using it to watch paint dry.

Any on glass yet?

I read that and smiled.


That had me literally laughing out loud.

GL

Nice update Tiddler

And from my house to Canada is just a short swim across Lake Erie so we are almost neighbors.

Just for an interesting factoid, last night I was doing a demo of my screen for a friend that built a screen from da-lite gray something or other, (I'll get the spec on it) but he kept telling me how no painted screen could compare to this high gain gray film. And he brought a sample 18x60 he had left. We compared it first on a white black checker board screen and it was about 2% brighter on axis and about 10% dimmer off axis. We then viewed it against a movie and the da-lite screen merged so close to mine if there wasn't the edge lines you couldn't really tell. It was a speck easier trying hot spot it seemed.

This guy came in loaded for bear and left saying how surprised he was that it was so close. He did comment on how I got my screen so flat. He said no matter how he stretched this film it always wanted to form a wrinkle later.

Then I told him this recipe of mine was one of the lowest tech of the DIY blends and that many contained metallic and mica and pearls along with mirrors and Light Fusion properties. He just said that's crazy and went home.

Your first shots illustrate the problem of applying a semi-translucent top coat over a contrasting base. The application would have to be absolutely perfect to make something like a 70% translucent coat of white over black workable. I'm curious to see how many rolled coats it takes you to get a uniform surface. By my thinking, the opacity of the top coat will have been pushed very close to 100% by then, and the base coat won't play much of a role. The white panel, however, looks ready to go as is.

So, you're also doing frosted mirrors? Cool, those can reach very high gains. However, with the thickness of 2nd surface mirrors, you're likely to see pretty bad haloing.

Looking forward to progress pics.

Tiddler

I think you are right on the da-lite material I tested it's a silver gray look and you are right about the texture. It was intentionally manufactured into the screens top surface, and like you seeing that triggered my mind off into the texture debate again.

The color match you did seems like the glidden came back pretty close to the wispy gray and also my silver leaf as to the 22/48 LB so I can see why it tested so close side by side. Another interesting side note I have found about paint matching over the years is I have taken samples in and color matched and they came back with a mix that I know had totally different stuff in it than the original. But the resulting paint is exactly the same.
Thanks for posting the data and the pictures the World Wide Web is getting excited. Last time I remember being so excited was when Geraldo opened Al Capones vault on prime time TV.

CoveX
Your thoughts and mine are very close on just how hard is it to paint a semi translucent top coat and not have a variability issue. In the case of LF and to my way of thinking if say the opacity ran between 40% and 60% due to human error in rolling or spraying and the resulting light had to make it thru that difference not once but twice in the case of the mirror. It seems the surface would show some areas richer in brightness than others. That's the speculation and what's left to be seen.
That's the reason I thought of the paint over glass test using the same skills Tiddler now has in even painting we should be able to hold the painted glass in front of the projectors beam and see the light transmissibility of the paint in the form of a back projection. We wont have a way to measure it once again but by comparison we will be able to see its evenness and by comparing the amount reflecting back FP vs. coming thru RP by eye we might be able to guess at the percent. That was the original idea anyway.

Tiddler

I viewed the tests early this morning and while I was cogitating my response I see you posted in with your observations. and once again excellent work on your part.

My first comment / observation is in agreement with yours and that is until the paint has a couple days to cure our responses may be premature in some regards. So I'm going to phrase my comments more in the way (what if) rather than what I see.

Things like hot spotting and gain will be variables until the paint cure is complete that is a known fact. Things like transparency of paint until cured is still a unknown at least in my mind.

All that follows are my thoughts and ideas and are in no way cast in stone at this point. When doing comparison testing without firm numbers connected to samples what we do is speculate and that is a valid method as far as I'm concerned but when we speculate about outcome it's important to use the same methodology in our starting points. And also the significant value of our findings. I'm not sure if many will understand the last statement I just typed so I'll try and explain it. In math and science there is the term significant used a lot and what that means is the results of a problem or experiment are only as accurate as the least accurate contributing factor. Without keeping significant in mind it's easy to wrongly assume very slight differences as meaningful. In this case maybe it's the paint changing during cure or the thickness of coats etc.

I know you are doing a excellent job of trying to control all that you have at your disposal and I'm sure doing better than I could do and have done with the testing I have done. For those out there reading this Tiddler is applying science to this in the truest form he's doing the tests without preconceived ideas of the outcome and letting the chips fall as they may.

So here are my thoughts in general.
We all agree now that testing apples to apples is important and one such apple is the shade of gray we start with. Because this shade is going to try and portray black as black at some point and when it tries to do this job it will be the area on the screen not getting much or no light. so no matter what process we use to make that gray its how it looks to eye or cam under very low light is what should be compared. That would be his first photo of the 3 samples under low room light. and the closer they look the more significant the outcome will be when we compare a screen shot with black in it.
The shots of the blank screens (on axis) under the cams flash point out what retro light will look like and give us clues to hot spotting but we have to keep in mind in these shots the light source and the eye are only a inch apart unlike a projector mounted high cam lower. Off axis flash shots I'm not sure tell us much as the screen closest is seing more intensity of light.
Then there are the screen shots of the image (test bars or flowers) taken one sample at a time don't tell us nothing much but when taken in groups tell a lot. It's not important to say look at two screen shots and compare color from one to another say on axis and off axis but rather look within one screen shot and compare samples. The reason being the cam being automatic and the placement not being perfect will adjust differently each shot. But when a set like posted above show the right sample darker on axis and then about the same off axis that indicates gain. We also have to go back to that first low light level gray shot and see if maybe the whole panel is starting off slightly darker. In this case even though the mixes were made with an attempt to have all grays equal at the start the far right one looks a bit darker from the start. So that has to be factored into the thought process. Curing of the paints might make them closer I don't really know at this point. When you compare the closeness of samples within a single picture and then only compare the findings between picture to picture you get a good feel for what is being learned.

So far Tiddlers latest test shows the black base vs white does darken blacks just a smidgen. It also shows the gray has a wider viewing cone and we can assume that because of a lower gain as shown above. The amount it darkened the black seems to my eye to be slight that combined with tiddlers statement that one more coat might have totally blocked the effect. That slight improvement in black could also be viewed as only a slight effect from the LF off the white. But this is just speculation at this point as the paint dries and knowing the black level change is so slight it could be a factor of significant values someplace else in the experiment.

All this does give me some ideas for Tiddlers spare time though that is if it don't rain. As he puts paint on the window glass wouldn't it be interesting to take a look as each layer of paint was added instead of waiting till the end. Hmmmmmm

Keep up the good work. The world awaits your next findings

Tiddler,

I may have mentioned this in another post, but I would still like to see the plain old UPW test panel in the screen shots against all of these experimental test panels.

The plain old UPW would be a good baseline/benchmark for all screen shots as it is probably the closest to a manufactured matte white screen.

I know I am speaking for myself, but I would bet people would like to see how these test panels compare to a basic Matte White screen that they would buy online or through a distributor and UPW would be the next closeset thing.

Thanks for the good work Tiddler,
Rob

My wife thinks I'm crazy at times I spend an equal amount of time researching snowplow designs and manufacturing methods of snowplows. Another strange hobby of mine. You have a gem there and we would much rather see a few days pass than a latex reaction.

Well based on the thrust of the glass and mirror project what if we projected to it just prior to more paint. Kind of a time laps of the successive coats and how they build to the best point for LF. We could then even go past the best point and be able to hopefully see the LF magic drop off.

As for high sides request for UPW I also think that would be good and tie in with my above post. By throwing a UPW into the mix it would show a stark example of the extreme. Based on how much projecting to the extreme looked different than some closely matched test samples might point out something we could call the total range because in a perfect world I still contend something like UPW would be a perfect screen paint.

Tiddler
Almost more fun than a man should have first thing in the morning.

Still digesting your morning offerings. And as always thought provoking. These photos along with the one you have taken over the last week go a long way to illustrating the effect of each paint mix. Some of the outcomes are very clear while some others a bit more puzzling. But it is clearly leading us down the correct path of understanding.

One of the easy things that pop out at you first is the last shots containing the white sample. Even in a light control room or with slight introduced ambient lighting the gray helping blacks is pretty clear no matter what mix you compare with. And yes in all cases some of the whites diminish but any newcomer will be able to judge the pros and cons of that choice from those photos.

I also believe the black vs white leads me to understand and also believe there is light fusion taking place to some degree. And the last two pictures comparing the mirror sample to the white IMO tell a lot. The straight on shot shows the sky brighter on the mirror than the white sample while having similar darks at the bottom of the photo.
The side chair shot same image shows the sky brighter on the white than the mirror and also shows the dark level brighter at the bottom.
This would lead one to believe there is a difference in viewing cones between the two samples and also the mirror sample is of a higher gain at the sacrifice of viewing cone. The interesting thing is that higher gain helped the brightness of the sky on axis but didn't wash out the blacks.

Like I said I'm typing while digesting still and thought may change as the day moves ahead. If this was (Myth Busters) we wouldn't quite be ready to stamp BUSTED yet.

But I wanted to chime in early and say good work. Will be interested in seeing others comments.