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View Full Version : Finished my DIY curved screen set-up with pics


tr6
11-04-07, 11:59 AM
First of all I would like to thank everyone on this thread who helped answer all of my questions to make my set-up possible. My main concern was would 2:35 work on my short throw set-up ( just under 10 ft from screen to lens, 45" height with a throw ratio of 1.47) and in my case, yes it will work. I wound up buying the Panamorph 380 lens and the Sony vpl vw60. After talking to Panamorph they said the lens will work with my short throw however I will get some pincushioning which is why I built the curved screen. I also built a manual sled from ideas I also got from you guys. I wound up covering the screen with black velvet material with self adhesive that I got from Mcmaster-Carr Supply, the stuff works great. Enclosed are some pics. Anyone thinking of going 2:35, GO FOR IT !!! the effect is unbeliveble. In the future I want to add remote control curtains for masking and maybe build a remote control transport for the lens, I used to hate 2:35 movies, now it's all I want to watch. Thanks again for all your help,
George

tr6
11-04-07, 12:16 PM
A few more pics I could not fit, The screen shots don't do it justice, it looks alot better in person,
George

DipakP
11-04-07, 12:34 PM
nice job
i am very envious
may i ask where you purchased the material from (maker, cost, etc...)?
I am planning on trying to do the same but was curious as to the cost savings this represents.
how did you do the radius?
again- kudos on a job well done.

tr6
11-04-07, 01:21 PM
Hello Dipak, I bought the screen material from the AVS forum which they got from Vutec. The material is a Vutec bright white with a 1.3 gain, the material measures 47" by 112" outer size which includes a 1" border with Velcro for easy installation. Viewing surface is 45" by 110" which is a 2.44 screen ratio ( thats the picture size that I got when I installed the lens, so I went with it).The Vutec material was $209.00, the black Velvet was $57.00 and the wood from Home Depot was about another $60.00. Total cost was about $326.00. After figuring out how many inches difference between the center of the screen pincushion and the edge using the broomstick method that I got from CAVX (in my case it was 3.5") I nailed 2 long nails 3.5" from a starting point on both ends of the 2 by 6 board that I used for the curve and nailed 1 long nail in the center of the starting point ( the starting point was 1.5" from the edge of the wood for strengh) the I simply put a long 1 by 3 piece of wood on the center nail and bent it over the other the 2 nails on both corners to get my radius. Then I used a marker to trace the curve which I then cut for the curve. Hope that helps, George

CAVX
11-04-07, 05:43 PM
Tr6,

Looks like a bought one after the flocking went on - well done :) I really like the way you taken the screen lit up first, then the actual screen shots from the same angle. Very cool. Send you photos to Alan and be added to the long official 235 thread...

Mark

oman321
11-04-07, 05:54 PM
Looks great tr6,

What did the edges of the curved 2x6 end up being? If your starting point was 1.5" and you went out 3.5" did it end up being 5" thick at the edges, thus shaving off about .5" off the vertical pieces as well?

The pic looks excellent, you should be proud and I'll probably be borrowing your design. Thanks for posting.

tr6
11-04-07, 08:36 PM
Hello oman321, yes the edges of the curve are 5" thick and so are the vertical pieces, I also had to cut the front part of the vertical pieces at an angle to meet the curve of the screen border.
George

Riblet
11-04-07, 08:42 PM
Very nice! I like the design for getting the smooth curve and rigidity from the L-shape wood support. But I am still unclear on how you attached the screen material to the frame. Velcro? Does that mean you had to purchase the screen material already pre-cut to your dimensions? Hmmm, that might be the way to go anyways since I am all thumbs when it comes to sewing material.

tr6
11-04-07, 09:36 PM
Hello Riblet, Yes I ordered pre-cut, the Velcro came already sewn on the viewing side of the screen in a 1" border, that's the way I ordered it from Vutec and then you simply attach it to the inside border from the back of the screen.

Riblet
11-05-07, 07:58 AM
Ahhhhh.... I like that even better than what I was envisioning, since it gives you a very sharp edge border. I am leaning towards a curved screen for my next setup, so that I can place the projector fairly close to the screen.

JDLIVE
11-05-07, 12:35 PM
Looks nice!

CMRA
11-06-07, 09:53 PM
Looks nice!

And short throw to boot. excellent.

CMRA
11-06-07, 09:59 PM
First of all I would like to thank everyone on this thread who helped answer all of my questions to make my set-up possible. My main concern was would 2:35 work on my short throw set-up ( just under 10 ft from screen to lens, 45" height with a throw ratio of 1.47) and in my case, yes it will work. I wound up buying the Panamorph 380 lens and the Sony vpl vw60. After talking to Panamorph they said the lens will work with my short throw however I will get some pincushioning which is why I built the curved screen. I also built a manual sled from ideas I also got from you guys. I wound up covering the screen with black velvet material with self adhesive that I got from Mcmaster-Carr Supply, the stuff works great. Enclosed are some pics. Anyone thinking of going 2:35, GO FOR IT !!! the effect is unbeliveble. In the future I want to add remote control curtains for masking and maybe build a remote control transport for the lens, I used to hate 2:35 movies, now it's all I want to watch. Thanks again for all your help,
George

George, just one question. Does the vw60 morph the image for you or was an external processor employed?

camarillo_cinema
11-07-07, 10:10 AM
George-
Very well done. I was wondering, the velvet from McMaster, is this the 45 - inch wide stuff?

BTW, I'm currently building a curved screen made from aluminum. Will be posting when it is finished.

Don

cjd
11-07-07, 11:53 AM
Great way to get the curve. After seeing your pics I went ahead and started with a 2x6 frame. However, while grabbing base-moulding for a family room project I happened to notice a rabbeted moulding (clear pine - the cap is rounded over on both sides, and the back has a single rabbet that starts full width and angles in for about an inch and a quarter) that i deemed perfect for a rear-stretched screen. And indeed it is. I'll snap a pic of the profile when I get a chance. What was nice about the shape is it provides a cleaner edge for the screen to sit against. Probably not critical, but it does work well :)

I DIY'd my lens. Throwing a 41" tall image from about 11.5 feet back. I'm still struggling with lining up the projector - it skews the right side still (without the anamorphic lens). But my hands were tired from stretching the screen last night so I didn't mess with it too much. Seating is at 10'. And man, is that a nice image. Perfect size.

C

prabhatb
11-07-07, 08:58 PM
Hi

It is a nice job tr6.

I have made my own curved screen as well. I used reverse calculation to find out the curvature needed. The anamprphic lens only created 2 inch deep in the curve (pin cusion effect) when projected onto to plain wall. Used deep and width to find out radius, using the constant radius calculated the segment heights at 1 feet apart. So you will fin my screen is curved very slightly. The screen is 15 feet wide, hence the effect.

Some photos:
http://picasaweb.google.com/prabhatb/DIYCurvedScreenForHD80?authkey=POsNp1tXOhU

nosdude
11-08-07, 01:12 PM
Hello Dipak, I bought the screen material from the AVS forum which they got from Vutec. The material is a Vutec bright white with a 1.3 gain, the material measures 47" by 112" outer size which includes a 1" border with Velcro for easy installation. Viewing surface is 45" by 110" which is a 2.44 screen ratio ( thats the picture size that I got when I installed the lens, so I went with it).The Vutec material was $209.00, the black Velvet was $57.00 and the wood from Home Depot was about another $60.00. Total cost was about $326.00. After figuring out how many inches difference between the center of the screen pincushion and the edge using the broomstick method that I got from CAVX (in my case it was 3.5") I nailed 2 long nails 3.5" from a starting point on both ends of the 2 by 6 board that I used for the curve and nailed 1 long nail in the center of the starting point ( the starting point was 1.5" from the edge of the wood for strengh) the I simply put a long 1 by 3 piece of wood on the center nail and bent it over the other the 2 nails on both corners to get my radius. Then I used a marker to trace the curve which I then cut for the curve. Hope that helps, George

I'm trying to understand how you guys figured out the curve radius. In the attachment is an exagerated pincusion. Is the area I marked as "a" the measurement we are talking about?...Thx

tr6
11-08-07, 02:23 PM
Hello CMRA yes the Sony vw60 does the stretch, it's one of the reasons I bought it. Hello Don yes I used the 45" velvet and still had some left over, the stuff worked great.
Hello nosdude. This is the advise that I got from CAVX on how to figure out the pincushion correction,
"The best way to "ray trace" is to project on to a flat surface first.
Take a stick (broom stick is ideal) and mark the top and bottom of the centre of the light beam on the stick. This is the smallest vertical part of the image suffering pincusion.
Move the stick to one end. The pincusion effect will have the light spilling over the tape markers.
Move the stick out from the wall until the tape now once again matches the light beam.
Measure that distance from the stick back to the wall. That is your distance for your screen.
Bend the frame (if possible) to match the distance at each end with the centre secured to the wall."
Hope that helps, George

nosdude
11-08-07, 03:13 PM
Hello CMRA yes the Sony vw60 does the stretch, it's one of the reasons I bought it. Hello Don yes I used the 45" velvet and still had some left over, the stuff worked great.
Hello nosdude. This is the advise that I got from CAVX on how to figure out the pincushion correction,
"The best way to "ray trace" is to project on to a flat surface first.
Take a stick (broom stick is ideal) and mark the top and bottom of the centre of the light beam on the stick. This is the smallest vertical part of the image suffering pincusion.
Move the stick to one end. The pincusion effect will have the light spilling over the tape markers.
Move the stick out from the wall until the tape now once again matches the light beam.
Measure that distance from the stick back to the wall. That is your distance for your screen.
Bend the frame (if possible) to match the distance at each end with the centre secured to the wall."
Hope that helps, George


Perfect explanation. Thanks.

prabhatb
11-09-07, 02:13 AM
I'm trying to understand how you guys figured out the curve radius. In the attachment is an exagerated pincusion. Is the area I marked as "a" the measurement we are talking about?...Thx

Hi,

I tried this way. Take your picture for explanation, I calculated the screen width (w) and Height (a).

Now I need calculate (a) at 1feet interval so that I will create studs and nail a frame over the stud to get the curved frame.

To do this, need to find out radius (r) from (w) and (a).

I used this calculator: http://www.1728.com/circsect.htm

Now keeping (r) constant I found (a) at various (w)=3feet, 5feet, 7feet etc.

Now I got (a)'s at 1 feet apart and cut the studs accordingly.

Hope it helps

Laserfan
11-09-07, 11:53 AM
the Velcro came already sewn on the viewing side of the screen in a 1" border, that's the way I ordered it from Vutec and then you simply attach it to the inside border from the back of the screen.Apparently the screen material has enough body/stiffness to it that this method still results in a smooth curvature to it? Sorry, I've never worked with screen material before.

I'm currently building a curved screen made from aluminum. Will be posting when it is finished.I'm very interested in this--I'm hoping to build a screen that is light enough that I can rotate it up-and-more-or-less-flat against the ceiling, likely into a soffitted surround. The wood the tr6 used would be too heavy for this I think.

GG386
11-11-07, 05:59 PM
So what came first, the screen or the projector? Since I have neither, here's what I do know- screen to be 10' wide, projector to be placed 13' from screen, mounting height to center of lens 7' from finished floor.

Given that- what would be the recommended:
1. Height of screen (10X?)
2. Depth of curve (between the right and left sides facing)
3. Mounting height of finished screen assembly (7' lens height)

Will different projectors change the numbers for above or can I go ahead and at least get my screen going. BTW, tr6 you did a nice job on that project!

prabhatb
11-12-07, 02:58 AM
GG386,

Most likely you would need to curve your screen if you are getting pincushion effect from using an anamorphic lens. If you don't use one, curving the screen may become a problem, it will give an effect opposite of pincushion effect. Of course you can live with it or mask it, but you make the call....

GG386
11-12-07, 07:50 PM
GG386,

Most likely you would need to curve your screen if you are getting pincushion effect from using an anamorphic lens. If you don't use one, curving the screen may become a problem, it will give an effect opposite of pincushion effect. Of course you can live with it or mask it, but you make the call....

This is exactly my point- If I use projector X, then in 2 years I may want to use PJ Y, then is my curved screen now rendered useless? Since I have commited to a CIH setup, (and ready to drywall next week), my plan is to recess the screen into my viewing wall. I could frame the R.O. and slip in the screen at a later time but what are the dimmensions for a 10' screen- is there a height that corresponds to the width? Any projectors (digital) that work better with scope?- probably the wrong forum I know but it can't hurt to ask:)

prabhatb
11-12-07, 08:26 PM
If you are investing on a good anamorphic lens, there is little chance that you would want to change it in x years, unlike a projector. With that in mind, your curved screen may not go wasted or need any change, since you will curve your screen to offset the amount of curvature created by lens. More or less even you change a projector (assuming that you would go with almost same throw distance etc.) and keep the lens, your curved screen will be useful for many years.

I have a optoma H80 and a DIY curved screen. My screen is really a big one - 15 feet wide. The height of the screen is little larger than it should be for a 2.35 aspect ratio. Since I have build a bigger (curved) screen, I am free to mask it in anyway to suit my projection. In my case actual projection is not 15 feet, but about 14.25 Feet. So I mask it both side , right and left and top and bottom with black 'Felt' cloth. Masking it will give you a real theater experience anyway.

nosdude
11-15-07, 12:36 PM
A few more pics I could not fit, The screen shots don't do it justice, it looks alot better in person,
George

Great pic of King Kong. Is that from a Blu-Ray or HD-DVD player?

tr6
11-15-07, 02:33 PM
Hello nosdude, It's a Toshiba A2 HD DVD player with 1080i output.
George

av noob
11-18-07, 07:10 PM
So if you know your screen size, throw distance, projector, and lens make/model, is there any way to determine the pincushion correction prior to actually putting the theater together? I am in process of demolition and then will begin the whole basement renovation (contractor actually) of which the HT will be a part, but I would like to figure out ahead of time the arc on my diy screen so I can be building it while the rest of the basement is under construction.

prabhatb
11-19-07, 03:07 AM
I don't think you would know for sure the curvature needed from just numbers (screen size distance etc ). Too many variables.

Laserfan
11-19-07, 08:46 AM
Apparently the screen material has enough body/stiffness to it that this method still results in a smooth curvature to it? Sorry, I've never worked with screen material before.What about this?

tr6
11-19-07, 10:30 AM
I don't know of any other way to determine how much curvature is needed to correct for the pincushion effect other than to have the projector and anamorphic lens in place, then you do your correction on your actual set-up. The screen material that I used is a Vutec Brite White with a 1.3 gain and yes it does have enough body strengh and stiffness to maintain a smooth curvature when installed with the 1" Velcro border to the inside border of the frame.

Brad Horstkotte
11-19-07, 11:40 AM
Looks great, congratulations on your hard work, and the payoff. I have a similar plan in mind, finally got my cave plans approved by the city, need to do framing etc., many months away from seeing an image - sniff - oh well, have a couple flat panels in the house to "tide me over" until then.

av noob
11-20-07, 04:20 PM
The screen material that I used is a Vutec Brite White with a 1.3 gain and yes it does have enough body strengh and stiffness to maintain a smooth curvature when installed with the 1" Velcro border to the inside border of the frame.


Is there a noticeable difference among the various screen materials? I bought some Pfifer 4500 for a 10' wide DIY curved screen. Has anyone used this to make a screen? How would you suggest attaching the fabric to a curved screen made similar to TR6's screen? The velcro seems like a good choice, but I am wondering if there are any other ways. I would hate to use up the fabric only to find that there are sags in the screen.

oman321
11-20-07, 06:28 PM
I have phifer 4500 and might use the velcro, if your just sticking it on you have to get the kind with the acrylic industrial strength glue I believe. tr6 (different material) and one other person who also had 4500 had the velcro sewn on. My other option is to use window screen supplies. In Home Depot and lowes they have tracks you can attach to metal or wood, you'll have two channels with which to feed the spline to secure the material. Still a ways off tough.

tr6
11-21-07, 05:50 PM
I recommend sewing the Velcro to the screen, this is the second screen that I have made with the Velcro sewn on and have had no problems, you can pull it pretty tight and it stays in place.

v1rtu0s1ty
11-25-07, 06:07 PM
What did you use to cut the curved shape on the 2x4?

tr6
11-25-07, 10:01 PM
I used a jig saw to cut the curve and then I smoothed it out with a belt sander. BTW it was a 2 by 6.

Drewbert
11-25-07, 10:13 PM
Very cool to say the least!
What screen did you use before this new one?

Laserfan
11-26-07, 10:40 AM
I don't know of any other way to determine how much curvature is needed to correct for the pincushion effect... The screen material that I used is a Vutec Brite White with a 1.3 gain and yes it does have enough body strengh and stiffness to maintain a smooth curvatureThanks for that.

I understand the technique for identifying & correcting for "edge focus" and apparently the closer the screen the less-well a pj's optics correct for a screen being flat, but...

Since PJs are designed & sold for flat screens, is it reasonable for me to assume that if my pj-to-screen distance is sorta in the middle of the recommended range for a pj, that "pincushion effect" is negligible? If anyone here knows/has heard of any "rules of thumb" in this regard by all means speak up. WAGs are welcome too! ;)

Riblet
11-26-07, 03:42 PM
I am fairly sure the pincushion being discussed here is the extra effect from using the prisms for horizontal expansion. This is above and beyond the pincushion already corrected for by the projector's lens.

Laserfan
11-26-07, 07:14 PM
I am fairly sure the pincushion being discussed here is the extra effect from using the prisms for horizontal expansion. This is above and beyond the pincushion already corrected for by the projector's lens.Oops, well duh! Does everybody concur? I figgered pincushion was anywhere, wasn't thinking in terms of the panamorph add-on. :o

GG386
11-27-07, 02:15 PM
If the lens does add some picushion affect and we curve our screen to account for it,then what happens when we passthru or remove the lens?

Laserfan
11-27-07, 02:22 PM
I think as has now been discussed in the CIH forum, there will be some negative impact as a pj's lens is designed to work with a flat screen. HOW negative will depend on the pj and throw/zoom etc.

Riblet
11-27-07, 02:41 PM
Since the greatest distance-from-flat will be at the 2.35:1 setting, there will be less focal distance change for the 1.85:1 setting. In other words, the negative effect without the prisms on 1.85:1 material is less than the positives of 2.35:1 with prisms.

Aussie Bob
12-09-07, 04:16 AM
I authored a spreadsheet for calculating pincushion distortion, screen curvature, throw ratio and lots of other useful stuff based on screen height and throw distance only (that's actually all you need to know, plus an understanding of optics - which is my job).

If anyone wants to try it out, PM me. PLEASE INCLUDE YOUR EMAIL ADDRESS IN THE PM.

CAVX's broomstick is a good practical method, but the spreadsheet approach allows you to simulate your installation before deciding on a room size, projector model or where you're gonna buy the broomstick. Plug in your room ideas and play.

Axel
12-09-07, 10:26 AM
I authored a spreadsheet for calculating pincushion distortion, screen curvature, throw ratio and lots of other useful stuff based on screen height and throw distance only (that's actually all you need to know, plus an understanding of optics - which is my job).

If anyone wants to try it out, PM me.

CAVX's broomstick is a good practical method, but the spreadsheet approach allows you to simulate your installation before deciding on a room size, projector model or where you're gonna buy the broomstick. Plug in your room ideas and play.

Bob, you got pm!
TIA!
____
Axel

GG386
12-09-07, 01:20 PM
I authored a spreadsheet for calculating pincushion distortion, screen curvature, throw ratio and lots of other useful stuff based on screen height and throw distance only (that's actually all you need to know, plus an understanding of optics - which is my job).

If anyone wants to try it out, PM me.

CAVX's broomstick is a good practical method, but the spreadsheet approach allows you to simulate your installation before deciding on a room size, projector model or where you're gonna buy the broomstick. Plug in your room ideas and play.

Now where talk'n. Thanks for the post, PM sent
Gary

actionPlant
12-13-07, 12:19 PM
PM sent.

Have to say too, I love the OPs frame. Great work, I think I'll steal the idea. :)

saldog78
12-18-07, 02:36 PM
I authored a spreadsheet for calculating pincushion distortion, screen curvature, throw ratio and lots of other useful stuff based on screen height and throw distance only (that's actually all you need to know, plus an understanding of optics - which is my job).

CAVX's broomstick is a good practical method, but the spreadsheet approach allows you to simulate your installation before deciding on a room size, projector model or where you're gonna buy the broomstick. Plug in your room ideas and play.

Really? That's cool. I thought you'd need to know the specific characteristics of the HE lens being used. Can't a higher quality lens produce less pincushioning than a lower quality one?

upm12345
01-06-08, 09:59 PM
Hello Everyone,
room where I am going to put a I am newx to the site and need some assistance.
I have a 132" Curved Screen. I am looking for the way to figure out the arch. I read on one site that I should be 6" from center point, but am looking for a formula or a way to confirm that. Any help would be appreciated.

oman321
01-07-08, 08:37 AM
Send a PM to Aussie Bob in post number 45 for a spreadsheet to figure out your curve.

mraub
01-12-08, 05:20 PM
George,

After having priced pre-made curved screens, your technique is sounding very appealing, even if I have to pay a woodworker to cut the curve in the 2x6.

I've read your explanation of how you marked the curve on the 2x6, but I can't see how what you did produced a curved line. Can you please give a more detailed explanation for those of us who got D's in geometry.

Thanks.

tr6
01-13-08, 08:55 PM
Hello Mike, After cutting the 2x6 to the correct length I drew a line 1.5" from the bottom of the 2x6 across the whole length of the board ( it was about 10 feet long), This is the starting point or center bottom of the curve, and I left that much room for strengh. Now go to one end of the 2x6 and measure up 3.5" (that is how much curve my screen has) from the line I drew and hammer a long nail about halve way (put the nail about 1" from the edge) and do the same thing on the other end (the nails will be 5" total from the bottom of the board). Now go to the center of the board and depending on how thick the board that you will use to draw the line is ( mine was 1/4") hammer another long nail halve way thru 1/4" up from your starting line in the center (2.3/4 from the bottom). Now take the board that you are using to draw the curve and put the center of it under the center nail and pull the other two ends up and over the top of the nails at each end and there is your curve. Now you simply use a marker to outline the curve.
Hope that helps, George

mraub
01-14-08, 12:16 PM
Thank you, George. That explains it so even I can understand it.

When setting up the proportions for your screen did you use as your horizontal measurement the width along the curved line or the flat width? It probably doesn't make all that much difference, but since I'm doing it myself I may as well try to get it correct.

The screen I'm thinking of making is a bit wider than yours and I'm thinking of maybe using a 2x8 to give me a bit more strength where the curve goes deepest. My biggest problem may be finding a piece of lumber without warps or twists. I doubt I'll be able to find of piece of poplar or oak in that size locally and the softwoods I see in the lumberyards seldom are straight at anything over 8'.

cnickersonjr
01-14-08, 02:04 PM
A few more pics I could not fit, The screen shots don't do it justice, it looks alot better in person,
George

Man this is a great setup. I didn't think making a curved screen could be this easy. I will have to give this a try.

My setup will have a short throw also, so I'll need a curved screen.

tr6
01-15-08, 08:56 PM
Hello Mike, I made the measurements on the width before I cut the curve, so to answer your question it would be on the flat width. I also went thru a few 2x6's before I found 2 good ones. Don't worry too much about the finish if you are going to cover it with the black velvet. Also how much curve are you going to do? You might get away with 2x6"s instead of 2x8's.
George

mraub
01-15-08, 10:36 PM
Thanks, George. I may in fact go with a 2x6. I went to Lowe's this afternoon and the chances of finding a straight, unwarped 2x8x10 seemed dim. The 2x6's in 10' looked much better. Since I'm not sure of the final configeration of my room, I may just basically follow your pattern.

In your photos in looked like you nailed a 1x3 to the front of the curved cut. I can see how that would give good reinforcement but wonder if you left the 1x3 in place on the finished screen. It looks like it might create a shadow problem, but maybe it doesn't.

Given that the price I got for a pre-made curved AT screen was near $4K, I figure I'm way ahead even if it takes me a couple of tries to get it right. And as you point out, black velvet covers many sins.

tr6
01-16-08, 06:35 PM
Hello Mike, I'm not sure I understand your question but if you look at the pictures I have 4 1x3s across all four sides of the front . This is what gives you the 3" border, then I installed the screen material with Velcro on that border from the back (Velcro is sewn on the viewing surface side of the screen material). There is no shadow problem, the screen sits flat on that border.
George

mraub
01-16-08, 08:30 PM
George, that make a lot of sense. The back side of the 1x3 give a good place for the velcro.

tr6
04-17-08, 04:24 PM
I used a couple of L brackets mounted on the wall studs (the frame is pretty heavy) and placed the top 2x6 on the L brackets, that way I was able to move the frame left or right to center it. (a few private messages asked me how I mounted it) Hope that helps, George

stef2
04-23-08, 08:53 PM
Really? That's cool. I thought you'd need to know the specific characteristics of the HE lens being used. Can't a higher quality lens produce less pincushioning than a lower quality one?


I also thought this statement to be true: higher quality lenses (pricier) advertise less pincushioning. Is it true or not? if so the curvature of the scrreen would also depend on the lense's ability to reduce this effect?

mandarax
04-24-08, 05:01 PM
TR6 .. Nice job. Looks great, and a very helpful post. I also like the TR6 in the garage.

Now I am trying to find all those that stated they were building an aluminum frame.

I saw that Brite White screen fabric from Vutec and it isnt all that bad.

Person99
04-24-08, 06:25 PM
I also thought this statement to be true: higher quality lenses (pricier) advertise less pincushioning. Is it true or not? if so the curvature of the scrreen would also depend on the lense's ability to reduce this effect?

From my research and what I've been told by those "in the know", the variance in pincushion between lenses varies from virtually insignificant to non-existent. In other words, they all pincushion about the same with the same image size and throw ratio.

syncguy
04-25-08, 04:31 AM
From my research and what I've been told by those "in the know", the variance in pincushion between lenses varies from virtually insignificant to non-existent. In other words, they all pincushion about the same with the same image size and throw ratio.

I was looking for pincushion data for various lenses. Could you please give more details or post a pointer.

My thinking is the same. The anamorphic lenses positioned for home use do not have notable correction for pincushioning.

tr6
12-29-08, 11:22 AM
Just a quick note. I just finished installing electric curtains for side masking on my DYI curved screen and I am very happy with it. I was worried that because of the curve the curtains would stick out too far, but it's not bad at all. Also I was able to program it into my Harmony 880. When friends come over for the first time I'll start the movie with the side masking closed for 16x9 and the remotely open it for Cinemascope, it's a really cool effect.
George

HDGTX
12-29-08, 01:15 PM
Hi George / tr6,

Which powered curtain track did you go with ?

How is the noise level during operation ?

Do you have two sets of curtains, one for masking 16:9 & 2.34 & another set for full closing ?


Thanks,
John :D

tr6
12-29-08, 03:43 PM
Hello John, I went with Curtain Call electric curtains model CL-800 which have the 24 volt motor ( I noticed some other companys had 12 volt),The motor is not too loud during operation. I only have one set of curtains which gives me my 16x9 when closed and 2:35 when fully opened. I also slipped metal rods in both ends of the curtains to give me a straight edge. Hope that helps,
George

HDGTX
12-29-08, 05:35 PM
George,

Thanks, thats the model (CL800) I plan to use. It is sold on powercurtain.com also under the same part number.

How far out from the screen surface did you mount the curtain track?

Thanks for sharing.


John :D

tr6
12-29-08, 11:48 PM
Hello John I mounted the curtain track about 6 1/2 inches from the wall (you need to get the longer mounts for this) and the actual curtain edges are about 1 3/4 inches from the screen surface when masking for 16x9. When the curtains are fully open for 2:35 they are a little past the screen surface and are about 1/4 inch out from the black velvet border.
George

oman321
12-30-08, 10:05 AM
Pretty cool tr6. I've had it in my plans to use the same remote curtain system exactly the way your using it.

I would have to mount mine to my soffit/ceiling above my screen, hopefully the track is pliable enough to follow the curve of my curved screen wall and therefore the screen.

Did you curve the track as close to your screen as possible, or does it go straight across? If I remember the back of your screen and wall are flat

Can you also tell me what is the thickness of the hardware (up and down)? I had to mount my screen higher than I initially thought so I don't have much space (about an inch or so) above my screen's border. I don't mind covering some of my screens border at the top because it is about 3.5" thick but I don't want to cover to much if I go with this.

Don't be shy about posting some pics of the new look :D

tr6
12-31-08, 11:57 AM
Hello Oman321, I did not curve my track, I don't think you can ( there are cables running inside the track and I think they would bind if you try to bend it). The mounting brackets are 2 inches long, but if you don't have room on the wall you could probably mount them on the ceiling. I also used a long board and covered it with black velvet as a valance to cover the track. Hope that helps,
George

oman321
12-31-08, 01:31 PM
Thanks. Hmmmm.. gonna need to bend though. My screen goes in 3" at the center from the sides but since I only need to go from the fully open to a 16:9 mask hopefully I can slightly arch without making it constrict the cabling. Thanks again.

HDGTX
12-31-08, 03:08 PM
oman321,

You might call some custom drapery shops in your town to see if they can bend your track for a small fee :). Not sure if it takes special dies or clamps for every shape of track to hold them so the track doesn't crunch up during the process. Let us know what you find out

John :D