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Discussion Starter #1
Just curious has anyone considered trying to get something that works similarly to the Black Diamond screens? Seems like even in a dark room they would offer a better black level due to how dark the base color is?
 

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Well I was thinking if there was a plastic sheet material that we could find locally that lets light through on one side, but has some sort of anti-reflective coating on the other that maybe it would work. Then behind that you'd have some sort of darker colored projection surface. I'm sure the real thing is a lot more complicated but was just thinking. I'd love to be able to spend 3k dollars on the real thing, but that's way out of my scope lol.
 

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There was an attempt to go down this path back in our avs days involving 3M films. It stopped when the films needed couldn't be found in the proper sizes.

There was a lot of discussion and research several years back at the avs diy screen forum. You may have to search for that stuff in the archives though as the current state is clogged disinformation and money making ventures.
 

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Alright, well thought it was an interesting screen and you are probably right that it's likely going to be expensive to try all these materials to find what works best.
 

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I have always believed that a modified version of the Vutec UHG screen could achieve the same thing as BD. Basically, Vutec's curved screen was a translucent material over aluminized mylar or mirror. It gave a gain of around 5 I think. I think if you put a dark translucent material or coating over the mylar you might be able to reduce the gain.
 

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I have always believed that a modified version of the Vutec UHG screen could achieve the same thing as BD. Basically, Vutec's curved screen was a translucent material over aluminized mylar or mirror. It gave a gain of around 5 I think. I think if you put a dark translucent material or coating over the mylar you might be able to reduce the gain.
Hi Hometheatershack! I got interested in this experiment when I stumbled upon this thread. According to me, this is a good idea in theory. A higher quality glass mirror reflects nearly 100% of the light hitting it, in my opinion you wouldn't find anything with more gain than a mirror, right? If you used a mirror as a projection screen you would obviously not see anything but a bright flare from the projector lens, but if we applied a ultra matte coating, wouldn't we get a very high gain screen with no color artefacts? Maybe hot spotting would be a potencial problem, but has anyone heard of someone trying this? I havent seen the Vutec UHG screen, but guessing it must have been some sort of matte semi translucent fabric or coating on top of the reflective surface.

As Ericglo states, putting a dark translucent material or coating on top of a mirror or mirror film ex. mylar may give us a dark screen with a fairly high gain? Mirrors are expensive and hard to come by in these sizes we're talking about, so, as Ericglo said, mylar might be a good option, even though it reflect only 60-80% of the light hitting it.

I'm thinking, MDF-board painted black > mirror film > translucent dark sun film > ultra matte coating.

Would love to have your comments on this idea!

Regards
/Patrik
 

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Hi Hometheatershack! I got interested in this experiment when I stumbled upon this thread. According to me, this is a good idea in theory. A higher quality glass mirror reflects nearly 100% of the light hitting it, in my opinion you wouldn't find anything with more gain than a mirror, right? If you used a mirror as a projection screen you would obviously not see anything but a bright flare from the projector lens, but if we applied a ultra matte coating, wouldn't we get a very high gain screen with no color artefacts? Maybe hot spotting would be a potencial problem, but has anyone heard of someone trying this? I havent seen the Vutec UHG screen, but guessing it must have been some sort of matte semi translucent fabric or coating on top of the reflective surface.

As Ericglo states, putting a dark translucent material or coating on top of a mirror or mirror film ex. mylar may give us a dark screen with a fairly high gain? Mirrors are expensive and hard to come by in these sizes we're talking about, so, as Ericglo said, mylar might be a good option, even though it reflect only 60-80% of the light hitting it.

I'm thinking, MDF-board painted black > mirror film > translucent dark sun film > ultra matte coating.

Would love to have your comments on this idea!

Regards
/Patrik
Hi Partik, welcome to HTS! :wave:

Simply put, there is no way to make a DIY Black Diamond-type screen. If the processes that make such a critter aren't machine-controlled you will almost certainly get too many imperfections that will show up during use. Even the real BD screens are disliked by many people for having negative visual artifacts such as sparkle or hot spotting. Eric's point was in trying to make a curved screen with similar attributes as a BD. The curve of the screen would help mitigate the hot spotting that will occur if a flat screen is used.

You may find links on the web to another DIY screen forum that purports to have a paint formula that will, in their words "meet or beat" the performance of a BD screen; but don't believe it. The claims of performance for that forums screen mixes are offered without proof of performance, and the few we have tested fell short of the promised performance.
 

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Hi Partik, welcome to HTS! :wave:

Simply put, there is no way to make a DIY Black Diamond-type screen. If the processes that make such a critter aren't machine-controlled you will almost certainly get too many imperfections that will show up during use. Even the real BD screens are disliked by many people for having negative visual artifacts such as sparkle or hot spotting. Eric's point was in trying to make a curved screen with similar attributes as a BD. The curve of the screen would help mitigate the hot spotting that will occur if a flat screen is used.

You may find links on the web to another DIY screen forum that purports to have a paint formula that will, in their words "meet or beat" the performance of a BD screen; but don't believe it. The claims of performance for that forums screen mixes are offered without proof of performance, and the few we have tested fell short of the promised performance.
Thanks for your reply Harpmaker!

I've read a lot about DIY diamond screens on the web, just as you said, it appears there are no way such a DIY screen could be built to a low cost. A swedish guy from the swedish forum "minhembio.com" has come up with a recipe named Black Screen™. (Search for "Black Screen from Sweden") I've only judged from the pictures I've seen but I must say I was impressed when he compared it side by side with the BD, but on the other hand, the processes of making the screen is very expensive but also secret.

Just curious to know, even if we won't be able to clone a BD, could we make a high gain screen with the help of a super reflective material such as a mirror? Still curious to find out what would happen if you put a matte coating on top of a mirror (I'll try that when I get back from my vacation). Trying to curve a mirror would most likely end up with seven years of bad luck, so I would bet hot spotting would be the greatest problem to deal with.

Have anyone heard of a DIY screen involving a mirror?

Regards
/Patrik
 

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Thanks for your reply Harpmaker!

I've read a lot about DIY diamond screens on the web, just as you said, it appears there are no way such a DIY screen could be built to a low cost. A swedish guy from the swedish forum "minhembio.com" has come up with a recipe named Black Screen™. (Search for "Black Screen from Sweden") I've only judged from the pictures I've seen but I must say I was impressed when he compared it side by side with the BD, but on the other hand, the processes of making the screen is very expensive but also secret.

Just curious to know, even if we won't be able to clone a BD, could we make a high gain screen with the help of a super reflective material such as a mirror? Still curious to find out what would happen if you put a matte coating on top of a mirror (I'll try that when I get back from my vacation). Trying to curve a mirror would most likely end up with seven years of bad luck, so I would bet hot spotting would be the greatest problem to deal with.

Have anyone heard of a DIY screen involving a mirror?

Regards
/Patrik
The forum I read about the Swedish Black Screen on is quite famous for painting mirrors on their DIY Screens forum. Unfortunately, they totally ignore the laws of reflective physics there and those screens don't work all that well.

If you are not very careful using a mirror as a screen substrate you will end up blurring the projected image to the point of visibly softening the image, even if a first-surface mirror is used. Think in terms of the path of the light rays striking the screen. Any diffusive front coating will start blurring the image as the rays of the image go through the coating; these rays will continue to diverge even after being reflected from the mirror and will be diffused again on passing through the coating on their way out. Any coatings used on the mirror would have to be very thin to mitigate this effect.

High gain dark screens have problems in a number of areas; they are known for hot spotting, image blurring, color changing of the image, and costing a fortune. They are niche products that are only worth these disadvantages in very special situations.

I don't mean to crush your spirit of invention, but please don't think you can break the laws of physics. Good luck on your endeavors! :T
 

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The forum I read about the Swedish Black Screen on is quite famous for painting mirrors on their DIY Screens forum. Unfortunately, they totally ignore the laws of reflective physics there and those screens don't work all that well.

If you are not very careful using a mirror as a screen substrate you will end up blurring the projected image to the point of visibly softening the image, even if a first-surface mirror is used. Think in terms of the path of the light rays striking the screen. Any diffusive front coating will start blurring the image as the rays of the image go through the coating; these rays will continue to diverge even after being reflected from the mirror and will be diffused again on passing through the coating on their way out. Any coatings used on the mirror would have to be very thin to mitigate this effect.

High gain dark screens have problems in a number of areas; they are known for hot spotting, image blurring, color changing of the image, and costing a fortune. They are niche products that are only worth these disadvantages in very special situations.

I don't mean to crush your spirit of invention, but please don't think you can break the laws of physics. Good luck on your endeavors! :T
Well, lets face it, this is complicated stuff :doh: I appreciate your comments on my wild ideas though! I'm really glad I've found this forum anyway, I have no plan of giving up trying to find the ultimate DIY screen ;) Unfortunately (for now) I have white walls and white ceiling, and the sad part is, there's nothing I can do about it (of course, technically I can, could paint them black, use black curtains etc. but as the only home theater enthusiast at home, these arguments are tough to win). Light bounces out from the screen, on to the white walls / ceiling and then back in to the projected image, destroying the blacks. A simple grey screen didn't give me what I was looking for, turned the whole image "flat" even though blacks got better. Would like to have a HC screen, reflecting the light back at the audience, not to the walls or ceiling.

Any DIY recommendations?

Regards
/Patrik

Edit: Found a thread here called "Mirror Experiments" in the DIY Development section, haven't posted five posts yet so I can't link, search for it! They discuss practically everything regarding mirrors and mylar as a base for a projection screen, check it out!

Also, English is not my native language (haven't even been to the states or any English speaking country except Scotland once), please be lenient with some grammatical errors and spelling mistakes may occur. //Patrik
 

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A mirror will not work well at all. Mylar, on the other hand, might. I've had some mylar for a long time but I've never done anything with it. It would be a real pain trying to get that attached to a substrate flat without bubbles. But it takes the gap between the mirror and the glass surface out of the equation.
 

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A mirror will not work well at all. Mylar, on the other hand, might. I've had some mylar for a long time but I've never done anything with it. It would be a real pain trying to get that attached to a substrate flat without bubbles. But it takes the gap between the mirror and the glass surface out of the equation.
High mechman! I agree with you, a first surface mirror is a must, thinking of what harpmaker said, you can't escape or change the laws of physics! Can't think of anything else than glass or acrylic glass to mount the mylar on and that would also be a significant cost. A company here in Sweden sells a reflective film, as mylar, that shrinks when heated. They recommend to stick the film on to a frame and then heat it up! That would cause the film to shrink a tension it self. Result? A totally flat first surface mirror to a reasonably low cost.

If you search for "DIY first surface mirror" you'll come up with some ideas of how to turn a standard mirror in to a first surface mirror! (or both sides mirror). Works by stripping of the protective sheet on the back side of a mirror. Qoute: To create a front surface mirror, coat one surface of your mirror with a paint remover/stripper that has the key ingredient Methylene Chloride in it.

Also a bit tricky it appears but it might work, might not.
 

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I know this discussion is old but I think it is still topical and I have something to add!

Firstly, just for information, Black diamond screens (made by DNP) use microscopic louvers printed into the material which is why that component of the design can't be achieved with a paint brush or roller. DNP is a large Japanese printing group mainly so they have access to large printing presses.

In terms of performance, even black diamond screens can't reach the standard they claim. It is great marketing though. There is no screen that works well in high ambient light with a standard home theater projector. They are too dim and the black version of that screen is only a 0.8 gain. The more popular 1.4 gain screen is a lighter grey color and neither looks like a plasma or even that different to other grey screens. The best either will do is look ok with a small side light on. If you look at candid user photos, you see a slightly less washed out picture in a bright room but not even close to perfect. Like I said, great marketing though.

There are some aspects of the design that can be replicated such as a near black screen surface. I will include some pics of the black-screen material I made at home. I painted my surface a glossy black. Under the black was a layer of aluminum that was already dry (the real BD screen is held rigid by a piece of aluminum sheet). When the black was dry, I added a layer of semi translucent / semi transparent screen paint using a spray gun to give it a smooth finish. The result looks like dark grey when not in use and black when on. It is really a 3 layer screen.

To test it, I had bright lights above it, another light directly beside it and the sun shining in through open blinds directly behind it. The sun light was directly in the projectors path which everyone will tell you is a tough situation for any screen. Instead of comparing it to matt white like SI does, I thought it would be more useful to compare it to a screen painted with screen goo, high contrast grey paint. This would be a standard commercial paint recommended for use where ambient light can't be controlled right?

The projector used is only a 2000:1 contrast ratio. Check out the candid photos. I think you will agree that the test room is bright and that I am achieving decent blacks considering how bright the room is? So how important are those micro louvers that you can't replicate? With a bright enough projector, not very important at all and I don't think they do that much.

I could do one more thing to make it closer to BD which is add a layer of glass at the front. BD knows that a clear image needs a smooth surface. Glass is a good way to give you a smooth surface if, for example, you covered the screen underneath with tiny printed louvers. It also adds some reflectivity which is helpful if the rest of the surface is not reflective black. The problem with glass, which BD also suffers from, is hot spotting so position of your PJ is important. A solution I haven't tried, which I think would work, is to use frosted glass and have a black surface behind it. The glass would still need to be semi transparent though. BD is a heavy screen and for this reason, I left mine without glass.

Let me know what you think of the pics. Sorry they are a little grainy. I add to downscale them to upload. The originals look super clear but you can still see the blacks.
 

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Rob,

Looking at the photos, it seems that most of the ambient light is behind the screen from the shadow cast on the flooring. It seems to be performing as well as a dark gray paint can. :T

As for your statements regarding the Black Diamond, I couldn't agree more. The only caveat being that it is my understanding that dnp does not produce Black Diamond screens anymore. At least that is what dnp told me a couple years ago.

Welcome to the Shack! :wave:
 

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Hi Rob!

Did you manage to paint the translucent paint evenly across the sheet? Translucent paints are extremely hard, if not impossible to paint. If the paint gets a bit thicker on one part of the screen, you will get hot spotting. I've tried translucent paint in big scale but I quickly gave up.

Regarding the glass, I've tried that too. Frosted glass is not the way to go, makes the image blurry and nothing else. I also tried using frosted film, gave me more gain but it also gave me a shimmering and sparkling image. Technically, if you had a bright enough projector, you could use a black painted screen as a projector screen, but yet again we're talking a super bright projector. If you take a completely black paper and put it in front of the projector, lets say a 15" screen, you'll get a great picture with awesome blacks.

Mechman, I've gotten some test samples of mylar and I will try to mount it on plexiglass later this week. I've mounted tinted films on cars before with good results, the trick is to use two or three drops of dish soap in 1l water and then use a LOT of the water and soap mix. You can't use too much of it, spray a lot on the surface you're going to mount it on, a lot on the film as well, and even on yourself and the surroundings to prevent dust getting stuck between the film and the glass.

/Patrik
 

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It's hard to see exactly how bright the room is from photos but I can tell you that the room is well lit from 3 directions. A good portion of the light is sunlight coming in from the large double window facing the screen. The projector is in front of the window and the test was done in the middle of the afternoon.

Other than being outside, it doesn't get much brighter than this. You can see how the "high contrast grey" screen from screen goo struggles to give a visible image. The black screen is watchable.


On the translucent paint, yes it was very hard to get an evenly painted surface using a roller. The best I achieved was using a screen printing roller which is solid plastic instead of soft foam etc. Even then, it only gave a good image when you stand back. In the end, I bought a sprayer from home depot for $80 which did the job easily and quickly. I feel like my bones are still vibrating from the noise of it.

It is a shame I had to reduce the quality of the image to upload them because what you can't see is how sharp the picture is. I wanted to see if it is possible to create a version of black screen technology at home and I concluded that it is. I also believe there are better ways to do it than this now I understand the principle.

I am currently experimenting successfully with a similar screen type which uses a charcoal colored rear projection fabric with a solid reflective coating on the back to turn it into a front projection surface. I want the front surface to be fabric instead of paint to make sure it is smooth. All of the high priced solutions advertise a "multi layered" technology although they tend to be somewhat evasive on further details. I have seen dozens of patents described for projection screens and very few of them from screen innovations and DNP. They are all there for anyone to read and it is worth doing a little research to understand the science when designing your own. You don't have to worry about patents for your own mix. The Sony Dynaclear uses a dichroic coating to make it "selectively reflective". Essentially a multi layered coating that only reflects red, green and blue light from the projector and nothing else. Who says it is impossible to make your own dichroic coating or to get a company to make one for you?

I think this is where home solutions fall down sometimes. Mixing paint doesn't always give you the properties of both colors. For example, red pigment is great at reflecting red light, but it also absorbs green and blue. Mix red, green and blue paint and you will probably absorb all of them and get a very dull image. That is why you sometimes don't achieve the increase in gain you might expect from mixing reflective paint like aluminum into your mix. The challenge is finding something to enhance reflectivity where you want it and not absorbing colors you do.

Mixing water based aluminum paint with white or beige gives me a grey paint. In theory, this is meant to have a much higher gain than just using a ready mixed neutral grey which is made from black and white pigment. The trouble is that I couldn't swear that the difference in gain is that significant. I'm sure others have had better results than me but there has to be a reason why aluminum paint isn't generally used in high end screens.

I bought some Speedball aluminum ink which is used for screen printing and some newton and windsor aluminum ink. Both will mix with acrylic or water based paints. I found a significantly greater improvement in gain than I was able to with Auto-air water based aluminum paint. also, with the speedball roller, I found it a lot easier to get a smooth and consistent finish. I couldn't tell you why but I have a feeling it is something to do with the greater saturation you get with ink over paint. Mixing the silver ink into white or beige paint and the end result still has a metallic look instead of turning to light grey. You still get a watchable screen without hotspots, only much brighter. Silver ink can even make black paint reflective enough, to use with the right projector, without turning the paint light grey. I am experimenting with this right now.

I am a fan of black widow mix generally. I added some aluminum ink to my black widow paint mix and it closed some of the gap with more expensive high gain screens. I have tried a lot of these commercial offerings btw and I am almost always disappointed. None of the big players have a right to claim "innovation" in this space in my opinion. The elusive commercial screen that works well in all conditions, with all projectors and at a price that doesn't singe our nose hairs, has not been created yet. DNP charge $25K for their flagship screen. It may be great, it is a shame that hardly anyone will ever know so it is irrelevant.

I will try and upload a video link to Youtube to show the black screen in a way that shows how bright the room was and where the light was coming from.
 

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Patrik

I am interested in what you were saying about frosted glass. Perhaps I can learn from your experience and save myself some time and cost.

Was the surface of the frosted glass you used smooth or rough? Did you try it with a smooth film over the frosted layer? Also, did you try it with a black layer behind the glass?

I ask because I found that taking some anti glare plaxiglass and painting the back with aluminum paint, gives you a watchable projection surface, even if the aluminum paint is not evenly spread.

People always warn against mylar because it has a mirror-like finish but I have wondered how it would respond with a thing translucent light diffusing layer on top. It is designed to reflect light. I have experimented with one way mirror window tint film. It doesn't do much for reflectivity once you add paint but it does give you a really smooth surface to paint on which helps the finished layer.

There are tons of window tint films on ebay specifically designed to reflect, absorb, or transmit light in a very specific way. The right combination could probably make a good multi layered screen.

I want to try it with a tinted layer, reflective layer and then use glass bead (powder consistency) as the front diffusing layer for a retro reflective screen experiment.
 

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BTW, I was thinking about a DIY optical louver solution and it occurred to me that this is how the privacy screens for computers work. 3m makes those micro louver film. I am getting a price on some custom sized ones. If anyone has one on their monitor, I would love to know what effect it has when you hold it in front of your projector screen?
 

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It's hard to see exactly how bright the room is from photos but I can tell you that the room is well lit from 3 directions. A good portion of the light is sunlight coming in from the large double window facing the screen. The projector is in front of the window and the test was done in the middle of the afternoon.

Other than being outside, it doesn't get much brighter than this. You can see how the "high contrast grey" screen from screen goo struggles to give a visible image. The black screen is watchable.


On the translucent paint, yes it was very hard to get an evenly painted surface using a roller. The best I achieved was using a screen printing roller which is solid plastic instead of soft foam etc. Even then, it only gave a good image when you stand back. In the end, I bought a sprayer from home depot for $80 which did the job easily and quickly. I feel like my bones are still vibrating from the noise of it.

It is a shame I had to reduce the quality of the image to upload them because what you can't see is how sharp the picture is. I wanted to see if it is possible to create a version of black screen technology at home and I concluded that it is. I also believe there are better ways to do it than this now I understand the principle.

I am currently experimenting successfully with a similar screen type which uses a charcoal colored rear projection fabric with a solid reflective coating on the back to turn it into a front projection surface. I want the front surface to be fabric instead of paint to make sure it is smooth. All of the high priced solutions advertise a "multi layered" technology although they tend to be somewhat evasive on further details. I have seen dozens of patents described for projection screens and very few of them from screen innovations and DNP. They are all there for anyone to read and it is worth doing a little research to understand the science when designing your own. You don't have to worry about patents for your own mix. The Sony Dynaclear uses a dichroic coating to make it "selectively reflective". Essentially a multi layered coating that only reflects red, green and blue light from the projector and nothing else. Who says it is impossible to make your own dichroic coating or to get a company to make one for you?

I think this is where home solutions fall down sometimes. Mixing paint doesn't always give you the properties of both colors. For example, red pigment is great at reflecting red light, but it also absorbs green and blue. Mix red, green and blue paint and you will probably absorb all of them and get a very dull image. That is why you sometimes don't achieve the increase in gain you might expect from mixing reflective paint like aluminum into your mix. The challenge is finding something to enhance reflectivity where you want it and not absorbing colors you do.

Mixing water based aluminum paint with white or beige gives me a grey paint. In theory, this is meant to have a much higher gain than just using a ready mixed neutral grey which is made from black and white pigment. The trouble is that I couldn't swear that the difference in gain is that significant. I'm sure others have had better results than me but there has to be a reason why aluminum paint isn't generally used in high end screens.

I bought some Speedball aluminum ink which is used for screen printing and some newton and windsor aluminum ink. Both will mix with acrylic or water based paints. I found a significantly greater improvement in gain than I was able to with Auto-air water based aluminum paint. also, with the speedball roller, I found it a lot easier to get a smooth and consistent finish. I couldn't tell you why but I have a feeling it is something to do with the greater saturation you get with ink over paint. Mixing the silver ink into white or beige paint and the end result still has a metallic look instead of turning to light grey. You still get a watchable screen without hotspots, only much brighter. Silver ink can even make black paint reflective enough, to use with the right projector, without turning the paint light grey. I am experimenting with this right now.

I am a fan of black widow mix generally. I added some aluminum ink to my black widow paint mix and it closed some of the gap with more expensive high gain screens. I have tried a lot of these commercial offerings btw and I am almost always disappointed. None of the big players have a right to claim "innovation" in this space in my opinion. The elusive commercial screen that works well in all conditions, with all projectors and at a price that doesn't singe our nose hairs, has not been created yet. DNP charge $25K for their flagship screen. It may be great, it is a shame that hardly anyone will ever know so it is irrelevant.

I will try and upload a video link to Youtube to show the black screen in a way that shows how bright the room was and where the light was coming from.
Patrik

I am interested in what you were saying about frosted glass. Perhaps I can learn from your experience and save myself some time and cost.

Was the surface of the frosted glass you used smooth or rough? Did you try it with a smooth film over the frosted layer? Also, did you try it with a black layer behind the glass?

I ask because I found that taking some anti glare plaxiglass and painting the back with aluminum paint, gives you a watchable projection surface, even if the aluminum paint is not evenly spread.

People always warn against mylar because it has a mirror-like finish but I have wondered how it would respond with a thing translucent light diffusing layer on top. It is designed to reflect light. I have experimented with one way mirror window tint film. It doesn't do much for reflectivity once you add paint but it does give you a really smooth surface to paint on which helps the finished layer.

There are tons of window tint films on ebay specifically designed to reflect, absorb, or transmit light in a very specific way. The right combination could probably make a good multi layered screen.

I want to try it with a tinted layer, reflective layer and then use glass bead (powder consistency) as the front diffusing layer for a retro reflective screen experiment.
You have some great ideas Rob, thanks for sharing!

Regarding the tests with frosted film: First I tried with a frosted film (somewhat rough surface) painted with a mix consisting aluminium and black paint on the back of the frosted film. The result was a dark grey screen with a gain of somewhere around (guessing) 0.8, though, the picture got to shimmery and sparkling due to the rough surface of the frosted film.

So, I tried with a smoother frosted film, but that did't increase the gain that much, no luck there neither. After a while I started having doubts of using a frosted film at all, they didn't help making a darker grey screen. The smoothest frosted film I found who didn't shimmer at all was the one I made my self. I simply sprayed a layer of matte coating on a transparent film, but as I said, frosted film didn't serve any purpose, spraying the matte coating directly as the top layer was the best way judging from my tests. I tried with a black layer behind the glass, but I only had the rough frosted film available at the time, but I guess it would simply give us a very dark low gain screen, I can try this tomorrow and get back to you with results!

Rob, regarding the anti glare plexiglass, even though it is an anti glare surface, do you see any reflection from the projector lens? What is the purpose of painting the aluminium paint on the back when the plexiglass is transparent? Also, do you experience a shimmering effect from viewing directly on the aluminium paint? Seems like hot spotting would be a fact unless you finnish of with a matte top coating.

I'm excited about getting started with the reflective films. My idea is following: Mount a reflective film (Mylar for example) on plexiglass or similar smooth surfaces (PET is a very good alternative, much cheaper than plexiglass), on top of that, mount a translucent slightly black tinted film and then finish of with a top matte coating. On the back of the plexiglass or PET glass, mount a matte black fabric or paint matte black in order to stop any unwanted light passing trough (a black background is much better than white in this case since we're only interested in the light reflected by the reflective film).

Regarding the privacy film, I think the viewing cone will be so narrow that you wouldn't be able to see the edges of the screen. What is your ambitions with the privacy film? If you get your hands on this privacy film, how do you plan to mount it? However, if it works I could imagine it wouldn't send any light outwards to the walls and ceiling, only right back to the audience (just as it does with a computer screen). I have my doubts though.

Rob, I'd love to see a youtube clip of your test! What is the gain of your test screen guessing?

Regards, Patrik
 
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