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Thanks Patrik

The purpose of painting the aluminum on the back of the plexiglass is to take advantage of the smooth surface instead of trying to paint a perfectly smooth surface which is not possible. Black Diamond screens have a glass front and my guess is that it is for the same reason. Also, anti glass plexiglass eliminates the shimmer. As for hot spotting, like BD, you will get some unless you position your projector on a different axis to your viewing angle. For example, a ceiling mounted projector pointing diagonally down towards the screen would work. If it was on the same level as your eyes then you would see the reflection. From the testing I have done with this, I would consider making that sacrifice because the results were so promising.

When it comes to films, 3M make a bunch that, on paper at least, sound perfect for our purposes. The problem seems to be the quantities you have to buy them in and therefore the cost. For a roll with a 60 inch width, they come in lengths of 100 feet and cost around $8000. Fine if you were starting a business but not so great for just 1 screen. Especially as need 3. ! reflective film, 1 tinted film and 1 light diffusing film. I bet the results would be good. The light diffusing film would take care of all hot spotting issues as that is what it is designed for. So that leaves us either trying to get enough people to make it worth it, or finding cheaper alternatives which I'm told are not usually in the same league as 3M products. As the old Zen Master say "we'll see". Either way, I am convinced that I want the front layer of my ultimate diy screen to be film instead of paint. The increase in image quality with a perfectly smooth surface is worth some sacrifices for me. Now that I have seen the Sony Dynaclear, I know there is no other way to go. Pro screen makers always talk about increasing contrast with "tint". I am fairly sure they mean tinted films as one of the layers in their"multi-layer" screens.

On the "privacy film", I want the micro louver effect. This is how BD and similar black screen technologies work in brighter conditions while not being massively higher in gain. They use those micro louvers to block light from certain directions and allowing it in from directly ahead (like your projector). That is one of the reasons why these screens have a narrower viewing cone than others. Some of these are also retro reflective which is another reason for the narrow cone but the cone would be narrow anyway so it doesn't matter for them. If you look at the reviews, they show a fairly steep drop in brightness (like 50%) when you get too far off center. In reality, for most people who have a large screen at home, the seating would be in front of the screen unless they have a very wide room and too much furniture. I guess those people wouldn't want any kind of retro reflective screen anyway.

On the privacy films, these work in the same way. They block light front the sides and allow light within a 60 degree cone to pass. As it is the same technology, I see no reason why it couldn't be adapted to the projector screens if you can get one that is large enough. I am getting a quote on such a film as we speak. I have asked for pricing on a custom 100 inch version. As it is a custom film, I am assuming that I will also be able to specify changes such as broadening the viewing cone if the privacy screen spec proves to be too narrow. 60 degrees though sounds similar to some of the high end screens anyway. One of the problems (in my opinion) with the commercial screen manufacturers is their desire to keep everything a secret so they can charge a lot of money for what is essentially a piece of transparent film with horizontal lines printed on it. That secret, while understandable, means they are limited to designs that preserve the secret. I was thinking that, just like privacy screens, the micro louvers film should be removable to give you options. Essentially the best of both worlds. When it is bright, you block the light from the sides and put up with a narrow cone. For the occasion when a bunch of friends come over at night and you need a wider cone, you take it off. This assumes you don't also use a retro reflective only screen. I say only because some of the glass bead screens I have been experimenting with are really bright when directly in front of them but are also still watchable from the sides if the room is dark.

On the gain of my screen, I am assuming you mean the "black screen" I pictured on this thread (I have posted a bunch on other threads too)? I don't have any special equipment to test this and I have trouble distinguishing performance in bright conditions between improvements caused by contrast vs gain. I would guess that the screen pictured is about a gain of about 1. That being said, next to a window on a sunny day, it is far more watchable that a screen I have with a gain of 2. Increasingly, I am finding that a higher gain on a white screen can make the problem worse. You have a higher gain to help with ambient light but without using some pigment to make up for the projectors lack of ability to produce a real black, you end up with a bright but still unwatchable washed out image. When I added aluminum ink (not paint) to the back, I saw an increase in gain to perhaps 1.4. I saw a similar increase when I added some aluminum ink to my black widow mix.

Based on my experiences, if given a choice between a high gain screen and a high contrast projector vs a high brightness projector and a high contrast screen, I would go with the latter if watching in bright conditions was my goal. I remember reading somewhere that after 5000:1 the human eye can't detect additional increases in contrast so when you see projectors with 30,000:1, this can only be measured with equipment and at 5000:1 it would look the same. I mention this because we are starting to see super bright professional projectors with 8000:1 contrast ratio which will do a lot more to help with light conditions. If you have a home theater projector with 1000 lumens and a 50,000:1 ratio, nothing will help with the curtains open. For me, black screens help you get a good image from a bright projector in a bright room. That said, the magazine could be wrong. Has anyone heard a different number for how much contrast the human eye can detect?

I have plenty of footage of my experiments. I will go and upload it this afternoon and post a link. I took the footage to show how bright the room was from all angles which you can't capture in a photo. I would caution that it is hard to see gain in video footage or photos as they always seem to differ from what you see in reality. They are good for comparisons though.
 

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As requested, here are a bunch of links to video footage of my black screen tests. I have tried to show how bright the room is in each case. The first two show a comparison with a grey screen. It is worth noting that the room was bright enough that It was tough to obtain a watchable image with any other screen types, including my grey fabrics. This makes it tough to find a good comparison for quality purposes but I guess that is the point.

The first one shows a half and half comparison (bottom half is screen goo "high contrast digital grey". The top half is a strip of an early version of my diy black-screen material):


2nd. Again for comparative purposes, a screen goo, high contrast grey screen with a strip of an early version of my black screen material. This was the test that encouraged me to keep experimenting with this method. I wanted to compare it to a high contrast grey screen to make the test meaningful. All white screens suck in light. The screen goo high contrast paint wasn't much better to be fair. Don't waste your money on it. It is high contrast in name only:


The next lot are all tests of various versions of the diy black-screen mix only. Some of them are cruder than others depending on where I was in the process. You will see some imperfections on the earlier versions but they all taught me something. Only the final version is totally free of imperfections as I purchased the paint sprayer. The rest were done with a roller which is hard a hell to get an even coating for translucent paint. There is also one which is just projecting onto black material with a bright projector for fun but the rest are all black-screen tests.


Lastly on the black-screens, one with a different angle - thought I'd try an early version of the black-screen by the window with the blinds open to see if being closer to the day light makes a difference:


For a bit of variation, check out this diy glass bead screen test. Powder sized glass beads over aluminum ink:


I know this one isn't in the least bit relevant to this thread but I think it's cool anyway. Check out my transparent glass TV:
 

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Really bright sunlight today so perfect for testing my tinted film concept for making a diy black-screen.

As a baseline, here is a video of my black widow screen with a bright projector to show how bright it is. Even the black widow surface struggles to look anything but washed out and that takes a lot of light. I am a black widow fan and it normally gives good results with some ambient light.


Check out some of these pics. The third shows a translucent light diffusing film for front projection with a black cloth on the back to stop light getting through.

The 1st shows light diffusing material used for rear projection. In my opinion, there is nothing in front projection that works as well as comparable rear projection materials in bright conditions. It's a shame they are so annoying to set up. I prefer the way rear projection looks.
The 2nd shows the same light diffusing material used for front projection. It looks washed out as it is far from opaque. The 3rd is the same material with a black cloth covering the back to stop light getting through. Much less washed out. Almost watchable!


The 4th shows a roll of simple dark window tint with a glossy white material on the back. This tint is far too dark but still a useful first test. It definitely works to a point and I see potential. This is a 5% tint which is barely see through at all. I have ordered some 35% and 50% tint to try (higher percentages mean less tint. dark limo tint is 5% and 80% hardly has any tint). This is to test my theory that high end screens achieve contrast with layers of tinted film instead of mixing darker paints into their mix. These window films are cheap. While not directionally light rejecting like more expensive filters, they are anti glare and non-reflective which should be perfect. As you can specify how much visible light to let through, it should only be a case of finding the right one. I believe that using layers like this instead of mixing paints will give stronger properties of each layer than I would get by mixing them into one painted layer. We'll see. Check out this video clip too.


The light reflection is from my camera, not the projector before anyone shouts hot spot!

The 5th was taken later on when the sun went behind some clouds and to room got a little darker. I used the opportunity to get another pic of my black widow screen to show that it performs well in ambient light (just not as much light as the black-screen). Still a solid performer!

The 6th pic is the results using a white surface in the same conditions with the same projector for comparative purposes. As expected, washed out and unwatchable, even with a bright projector.

Now check out this clip showing the light diffusing material with a coating on the back of aluminum paint. It's hard to tell exactly from a clip but it looks great. So clear and bright. The only thing is that after 5 layers of that auto-air aluminum paint, light is still getting through. I'm not a huge fan of this brand for that reason. I think that 5 layers of any paint should stop light getting through. If I'm relying on this paint for reflection when mixed with other paints, am I loosing some of its effectiveness if the other paint is opaque and dominates over the aluminum??? It makes me want to redo the black widow with an additional 5 layers and twice as much aluminum paint to see. ...


I am going to follow up with a few more pics in a bit.
 

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For comparative purposes, some more pics taken at the same time as the ones in the last post.

Pics show a comparison with my diy black-screen mix, diy black-screen next to my black widow screen and the tinted film again.

Also, as a small warning to others, I have included to pics of Rosso screen materials. Rosso's black front projection fabric, which their website describes as "perfect for front or rear projection" is possibly the least reflective material I have ever seen. Look how dim the image is up close with a 7000 lumen projector. The asthmatic colors are barely visible. With the average home theater projector, you wouldn't even know it was on. Stay well clear as tempting as it is to try their relatively inexpensive screen fabrics. They clearly don't test them themselves so you can't trust the product descriptions on their site. It's easy to see why I am skeptical about claims that manufacturers make about their screen materials. The fine line between exaggeration and lying gets crossed regularly as they know we have no way of measuring their claims on gain etc. Most people don't have a second screen for comparison either.

Rosso's silver fabric, which isn't even close to silver, is also pictured. It is more of a light grey color sort of works in a washed out kind of way. It looks the same for both front and rear projection and may be better with a black backing although my attempt to try this didn't give much improvement to date. It's a shame, Rosso are a well known company and I had no reason to no believe them before. They sell 20 different screen fabrics with multiple colors of each. There is no reason to claim a materiel works for projection when it doesn't. I am going to try stretching the "silver" to see if it can be used as a layer of a high contrast screen.
 

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I have a question...

It is well known that white color is the most forgiving and easy to use in the calibration process. How about black color? Did you try to calibrate your projector? Did you notice any undesirable and unrecoverable color shifting even after using RGB or cms controls?
 

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This is great Rob!

Thanks for your pics and videos, I have to say I am impressed, though I have some questions. You mentioned you used a 7000 lumen projector when testing the Rosso black projection material, did you use that projector for all the other tests? If not, what projector was used during the other tests? As you demonstrated, it's possible to get a good picture using a bright enough projector and a completely black projection surface, I'm asking since the black screen test and the completely black surface test was quite similar.

I'll get back to you tomorrow after some sleep, can't process all this information you have given us this late at night, but I appreciate all your effort you have put down on this, it's great! :T

/Patrik
 

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Good question Yiannis. The reason they say white is "forgiving" is because, in light, it is a mixture of all three primary colors your projector uses to make up its image. As odd as it sounds. Mixing rgb light gives you white. In pigment, like paints, they appear the color they are because that pigment is most efficient at reflecting that color. Something that is great at reflecting red, will appear red. That is as far as my understanding of how eyes work goes. Red isn't red, it just reflects red light into your eyes. White is easy because it reflects the broadest range of colors and doesn't block any of the primary colors. Adding color will have the effect of enhancing the reflection of one of the colors and blocking another. Yellow, for example reflect green and blue but blocks red (or something like that). This leaves is in a pickle for screens because projectors can't project black so unless its dark, the only way to get black is by add pigment to the screen. Now, white isn't the only thing that has good reflection across the visible light spectrum. Some metals like aluminum and silver can reach 98% of the visible spectrum. This is why grey screens are ideally a mix of white or light colored paint and aluminum paint. Make the same grey color using black and white and you will see a drop in brightness. The key take away is that 2 aspects have and impact. Color is 1. The material properties are the other. There is also a difference between a color, and something that looks the same, but isn't - like black screen material. It doesn't work like other paint methods. The dark color may look grey or even black but it is actually multiple layers which are separate that trick the eye into seeing a single color. In this case, there is a light diffusing layer at the front, which is a translucent white. This layer is the screen surface for all intents and purposes and is as "forgiving" as any white screen. Underneath the light diffusing layer is a layer of tint which on its own would be a translucent black. This layer ideally lets a good portion of light pass too. When the projector light shines through the translucent white layer, you can see the black under it. As black is an absence of light, think of it as the projector just being off wherever the screen should be black. With a white screen, with the lights on, that would look grey at best. With the black tint showing, it now looks black. Behind the tint, there would ideally be a further reflective layer that covers the visible spectrum. Tint can let through 5% to 95% depending on which one you use. This will have the effect off letting more light and therefore gain through or less light and more tint for higher contrast. The front may look gray or black but it is really 2-3 separately layers which are white, black or silver. No of these will have the affect of change the color balance in a noticeable way.

Now, these screens are for bright conditions. In such conditions, white is actually the least forgiving. It is very difficult to achieve anything but a washed out look, let alone accurate colors. It is only the most forgiving in a dark room. As for calibration, I find these days that if you have a bright enough projector, you can achieve a watchable image on almost any flat, even solid color. As long as there is some reflectivity and light diffusion. Some of my projectors have settings for different colored walls including red, green, grey, beige, blackboard and whiteboard. I think that is a long winded way of saying, no, no issues with calibration from color shift. Paints with mica pigments have more issues with color shift I believe. If you can make black work, I think colors look much brighter with better contrast.
 

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Now, these screens are for bright conditions. In such conditions, white is actually the least forgiving. It is very difficult to achieve anything but a washed out look, let alone accurate colors. It is only the most forgiving in a dark room. As for calibration, I find these days that if you have a bright enough projector, you can achieve a watchable image on almost any flat, even solid color. As long as there is some reflectivity and light diffusion. Some of my projectors have settings for different colored walls including red, green, grey, beige, blackboard and whiteboard. I think that is a long winded way of saying, no, no issues with calibration from color shift. Paints with mica pigments have more issues with color shift I believe. If you can make black work, I think colors look much brighter with better contrast.
Thanks again for the info!! It's a bit out of my league of knowledge on the matter but nevertheless it's always useful learn new things..(the first part kinda reminded me a paper of XRite's which talked about colors and perception).

I can see your aim is practically to achieve a high contrast screen for very bright environments. However, for obtain such results you used many many lumens. Now, if we are going to stick to H.C. projectors, i think it would be quite difficult to find so much light at affordable prices. I believe, nowadays, a ~2000 lumens projector has become the standard to industry and that due to 3D. Then, it's the matter of size as well...how many lumens would you need to fill up according to standards a 100'' black screen?:scratch:
 

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I only used the 7000 lumen projector for the Rosso after failing to get an image with anything else. I was using a 2500 lumen projector for the rest of the tests. There would not be much achievement in creating a surface that didn't work without 7000 lumens. That said, I haven't tried the latest versions with my lower brightness projectors in the 700 lumen range. I can if you are interested to see how they do. My guess is that they will work with some room lights on but probably not with sunlight shinning in like in these pics. With the Rosso, even 7000 lumens wasn't enough...

Now, check out the last set of pics. I have made more progress. This DIY black-screen has a material front layer instead of paint which is a lot smoother and gives much better results. I started with a piece of white translucent light diffusing material. On the back, I added 7 layers of aluminum paint (which was how much it took to stop it being totally transparent for some reason. The front appearance then changed to dark grey. Not dissimilar to the black diamond 1.4 gain material in color. Even that didn't stop light slipping through so I added a layer of black paint to the back which did the job. This changed the front appearance to a darker grey. Almost black which is the effect we are going for. The first pic shows the appearance when not in use. I left a bit without black so you can see the difference.

Next are 4 pics of the fabric in use. I know it looks like I'm obsessed with that movie "the hunger games". I'm not. It is just one on Netflix that I know is 2.40:1 so you can see how good the blacks are on the black borders. Weirdly, the angle of the pic makes it look like I have a deformed hand which I don't. You can see in the later pics that my hand is normal, not a weird mangled claw. The last pic shows it working next to a piece of white material which, as normal, looks washed out in this light. It sounds like I hate white screens. I don't. I use one myself when the room is 100% dark for movie night. It is just necessary to remind us what we are comparing the black-screen too and that no white screen gives a good image in these conditions. We are talking blinds open during a summers afternoon here.

I should post a pic with the 7000 lumen projector on white to show that the image still looks washed out in a bright room. Anyway, the latest black-screen attempt is easily the best to date. I'll post some videos when I get around to it. I love the way it looks though. Its so bright, clear and smooth. I'm tempted to make myself a new screen with this method before I've finished my experiment but I'll wait. I will take delivery of some new tinted film, reflective film and light diffusing film in a few days and that will be the real test. Practically no hot spotting so far btw. Also, the end result won't rely on my painting skill (thank god) so it will look more professional and less like something a 4 year old would stick on the fridge with a gold star.

Also, I spoke to the micro louvers company today. They came back and said that the largest they make them is 55 inches. I said "I know, that's why I asked for a quote on a custom order". They said "oh yeah". So they have gone away again to get me a price on a larger piece. I am not that hopeful with this company though. I'm not dealing with rocket scientists. I may have to find a new manufacturer...

Look out for a new you tube video of the latest black-screen material in a little while. And if anyone can steel a privacy screen for testing, I would love to know if it works in the mean time.

Rob
 

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The lowest I have tried the black screen on is a 2500 lumen projector. I have some lower powered devices too. I will try them and post some pics so you can see. They will work, it's just a case of how much light they let you get away with. In general, if you have a really bright room (like sun light). You will need a brighter projector than 2000 lumens. This is true no matter what screen you use or how much you pay for it. Put the money into more lumens first. It is true that my aim is to get good contrast in a well lit room. I use a 3000 lumen projector for movies. Now, there are degrees of benefit. While nothing will make 2000 lumens look great in sunlight, the black-screen might give you a none washed out image with good blacks with a couple of room lights on in a scenario where you otherwise needed total darkness. I doubt there are Many projectors where this method wouldn't work at all. These aren't low gain screens.
 

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Just for you.

I tested the black-screen with my smallest projector. This thing is a real piece of cr*p. It was meant to put out 700 lumens when new about 6 years ago. It hasn't had a new bulb since then or anything so I think you'll agree this is a good test to see if the black-screen works with lower powered projectors.

There is no daylight at this time so the ambient light is from two room lights. One above and one to the side. Both fairly bright. More ambient light than you'll see in any BD test!

Check out the size difference between the 700 lumen and the 7000 lumen projectors!

I included a pic showing how this little thing struggles to produce even a small image on the white wall/screen in this level of brightness. On the old black-screen, it manages a respectable image, even on some of the difficult dark scenes in the hunger games. With the new black-screen material, the results are even better. I also show this compared to white material for comparative purposes. Bottom line is that is works and lets you use a low powered asthmatic projector with the lights on. It gives much better results than the white wall or white screen, even against a much smaller image. On the black-screen, the device is putting out a respectable 90 inch image which was unheard of with this device in anything but darkness.

Here is a link to a video clip to so you can see the conditions.


If your projector is less bright than this, time for a new one!

Rob
 

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Thanks again for the info and the analysis. You 've said before that you have also the Sony screen. I would be very interested to read your feedback against the black screen.:)


(pics would be most appreciated)
 

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I can get some pics of the two side by side. As it stands right now. I prefer the look of the dynaclear if I am directly in front of it. As soon as you move a little off center, I prefer my diy mix. I won't be able to tell properly until I'm done experimenting and make my finished screen. The sony is really smooth and I won't get that kind of smoothness with the diy until I make a fabric version. Paint is never going to be as smooth. Also, Sony is only 80 inches and curls at the edge. If I could get the material, I would make my screen out of it but I can't so diy it is.
 

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I can get some pics of the two side by side. As it stands right now. I prefer the look of the dynaclear if I am directly in front of it. As soon as you move a little off center, I prefer my diy mix. I won't be able to tell properly until I'm done experimenting and make my finished screen. The sony is really smooth and I won't get that kind of smoothness with the diy until I make a fabric version. Paint is never going to be as smooth. Also, Sony is only 80 inches and curls at the edge. If I could get the material, I would make my screen out of it but I can't so diy it is.

I believe too that Dynaclear does a pretty good job in both environments with all of its pros and cons. As you, i couldn't stand the curve on the edges, so i cut it off and and i am going to attach it on a laminate or something like that using an adhesive two face tape. I don't think that i will resolve the hot spot problem but at least weakened a bit the effect. As far it concerns its performance, there's a sparkle problem on high brightness scenes and the over glass sensation that gives a kind of weird look at the image. On the other side, it is still a mystery, at least to me, how they achieved a low profile like that (i assume that the surface should be primed first and the painted) and what type of paint they used.
 

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I can get some pics of the two side by side. As it stands right now. I prefer the look of the dynaclear if I am directly in front of it. As soon as you move a little off center, I prefer my diy mix. I won't be able to tell properly until I'm done experimenting and make my finished screen. The sony is really smooth and I won't get that kind of smoothness with the diy until I make a fabric version. Paint is never going to be as smooth. Also, Sony is only 80 inches and curls at the edge. If I could get the material, I would make my screen out of it but I can't so diy it is.
As I said, great work Rob, after watching your vids I'm convinced that your DIY formula is the best I've seen so far! When you say fabric version, are you referring to the experiments with tinted films & mylar we talked about erlier? What kind of light diffusing films are you using, 3M Diffuser film? I'd like to know how rough or smooth the film is. As I mentioned erlier, I tried with frosted film, not 3M though, and I experienced a shimmering / glittering effect, looked somewhat grainy.

I made a sample yesterday with a reflective /mirror film with a reflectance of 57%. The film is transparent, often used in office buildings for privacy but also to keep the heat out, anyway, I mounted the film on a piece of plexiglass and then I sprayed a matte coating on top. To prevent any light passing trough I placed a black fabric on the back of the plexiglass. The result was a light grey screen with a bit higher gain than my kingpin screen with a gain of 1.0, but also a bit sharper.

I'll get back to you later with some pics!
 

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Things have moved very fast in this thread the last couple days!

I have a comment regarding the photos and vids. Using a 7000 lumen pj to show a black screen image that is very small - screen wise - would be very simple to do. I'd guess your screen size in a lot of your images is roughly 60" or less diagonal where your showing the materials. Meaning your fL at your samples is somewhere in the neighborhood of what? A little less 700fL? Even if the ANSI Lumen rating for this pj is off by a factor of 2, you'd still be hitting the samples with a little less than 350fL. No offense, but I could make most anything look good with those numbers. You could use a solid black screen and it would look good.

Several years ago at avs, a member named budXXXX (replace the X'x with numbers) announced his black screen wonder and showed pictures of the screen in action. Most folks thought that it was the greatest discovery ever! However it was really just a practical joke played by bud. He made a very small black screen and took macro shots of it very close to his pj. Small screens being hit with a ton of lumens really shows nothing.

I'll read through more of this today, but so far, I haven't seen anything that I would consider a breakthrough yet. :huh:
 

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I doubt they used paint on the Sony. I am guessing it is printed on a litho press and then additional layers added on some kind of digital press like an hp indigo. It you look closely, it almost looks stitched. Over the reflective material is a criss cross of darker lines. Perhaps over the dichroic reflective surface, the dark lines act as as a hexagonal louver on a tiny scale. It makes a great travel screen (not that I ever travel with it). It could have used a little fiberglass backing. I was thinking of using a layer of carbon fiber to keep it straight.

Btw, I found a places that has larger micro louver films at a price that doesn't take them out the market. When I saw the 17 inch 3m product for $300, I was starting to think that larger ones would stop it being worth it. The new place had 65 inch ones for $150 and offers custom sizes so I will get a quote.
 

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I was using a translucent rear projection material which is similar to the 3m product but a lot cheaper. I haven't taken delivery of my 35% tint material yet or the reflective film. The fabric version pictured only has a fabric front layer. The tint and reflective layer are made with paint in this version. In terms of image quality, it is most important that the front layer is smooth. The light diffusing effect on the material I used had no visible hot spots but I wont know for sure until I make a larger version and watch from a normal seating position. I could use an assistant to get better pics....when it comes to hot spotting, it can normally be solved by repositioning the projector on a different plane. Of course this isn't possible with some retro reflective screens so the quality of your light diffusing layer will be key.

At some point I will make a choice on which features are most important to me. Projectors seem to be getting brighter while maintaining good contrast. I was looking at a device with 10,000 lumens and an 8000:1 contrast ratio. Home theater projectors catch up with the pro devices eventually. There will come a point where gain won't be an issue but we'll always need contrast from the screen with the lights on until they learn to project black. I remember reading a post on a science forum where someone was asking about making a darkness projecting device. Everyone made fun of him and said "they already made a device that brings darkness, it's called a light switch".
 
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