Introduction

This thread is intended to provide a place to openly discuss ways to make a very white screen. It is also a place to discuss near white screens that are intended to provide some low levels of ambient light tolerance.

In the first few posts I will try to keep a summary of the ideas that get tried and are considered successful.

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Summary Of Solutions - NO Painting

Blockout OR Blackout Cloth: This a very common solution for making a good stretched fabric matte white screen. It is simply blockout cloth, which is normally used to line drapes, stretched over a frame. Click here to see a very nicely documented BOC Screen Build. In the next couple of photos you will see one of the most clever ideas I have run across yet. This would do MacGyver proud!

Click to view attachment

Just remove the clip handles and there you have it. There are many variations one might make to this very simple design, but the key item that impressed me was the use of very common paper clips to attach the BOC.


Click image to view full size.


White Laminate Material: This solution has proven to be very effective. There is really only one Brand and color recommended. That is the Wilsonart "Designer White" in a matte finish. For the folks here they may find that laminate that is considered too shiny might be quite workable with your projectors. For example I tried a sheet of Formica "Brite White" in a matte finish. With my HD72 it would hot spot but it might be OK with a 200 lumen projector. If you live in the Ottawa area drop me a line because the Formica sheet is collecting dust in my garage. I would gladdly give it to anyone wanting to try it with a DIY projector.

Parkland Plastics "Polywall": This is a plastic material about 3/32" thick. It is meant to line shower stalls. One side is smooth with a low luster sheen. It has been used by many people as a matte white screen material.

White Vinyl Panel (Do-Able) : This is a sheet product made by DO-ABLE Products INC. and sold in ceentral and western regions of the USA, at Home Depot. It is a hardboard backing material with a matte white vinyl coating on one side. It is very inexpensive and effective if you can find it.

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Summary Of Solutions - Page 2

Some of the solutions will not be painted.

Some may not even be proven.

But hopefully they will all be interesting.

Summary Of Solutions - Page 3

I know I may seem optomistic trying to reserve 3 or more post for the summary of solutions but the number of images is limited and I like to include images because they do convey a lot of information that is often difficult with words.

Let's Open The Discussion Now

There have been a few developments that I thought the members here at LumenLab would be interested in. The first is a report from a member at AVS, tonywood, regarding the use of Behr Interior UPW Flat Enamel #1850.
I have not really pushed the Behr 1850 because I have found it does not level out as well as the Behr 4850 but it seems that the use of a foam roller could be the trick to applying this paint.

As anyone who has been following The Black Widow Wars thread will know, I was forced to use the Behr 1850 tinted gray as a reference in the comparisons to various Black Widow (AAA) clones. As a result of AVS member bud16415 scrutinizing those photo comparisons, he requested that I try adding some sheen to the 1850 by adding some satin polyurethane. I did this fully expecting the result to be some hot spotting. Much to my surprise the Behr 1850 + Satin Poly did not demonstrate any more tendency to hot spot than the BW-AAA-Valspar-Flat-Enamel. This is demonstrated in the following photographs:

Camera Flash


Projected White Light


The ratio of Behr 1850 to Minwax Satin Polycrylic was 4:1. I used this ratio because it seemed a logical choice, adding 8oz. poly to a quart of paint, and it was not too aggressive. In addition to increasing the surface sheen it also had the very desirable effect of thinning the Behr 1850. The addition of polyurethane or in this case Minwax Polycrylic causes the paint to level out to a much smoother finish.

So how is any of this related to the members here at LumenLab. First of all with lower brightness projectors, ~200 lumen, you can push the sheen a bit more without getting hot spotting issues. There are two simple ways to increase the sheen of a painted screen. The first is to use a satin or even an eggshell finish paint, the other and I think better approach is to add the sheen by mixing some satin polyurethane with a lower sheen paint. I think the addition of satin polyurethane is a superior approach due to the fact that it also causes the paint to level better and the sheen it introduces has a sort of depth to it due to some degree of translucents be imparted to the paint.

All of the Behr UPW paints 1050, 1850, and 4850 are very white. In the past I have encouraged some experimentation with mixing the Flat or Flat Enamels with satin UPE to achieve the ideal sheen level. I would like to revise that and encourage you to work with a combination of acrylic paint and Minwax Satin Polycrylic. This approach was pioneered by bud16415 at AVS. In his thread A Simple Screen Paint Solution, Bud outlines a method of determining the best level of sheen to use for any particular setup. Basically you apply a coat or two of the paint without any satin poly added. Then you make up a top coat of paint + poly. You apply successive coats with higher ratios of satin polyurethane until you get hot spotting. Then you back off to the last ratio that did not hot spot. You can either do this on the full screen or on a sample panel. For the purposes of detecting hot spotting I would suggest 4' x 4' sample panel.

In addition to the Behr 1050, 1850, 4850 acrylic paints, you could use the Kilz2 primer to get a slightly less white but fairly neutral shade that would provide some degree of enhancement for black levels. Then by adding the Minwax Satin Ploycrylic in increasing ratios you look for the hot spotting level of sheen and back off. This technique of Bud's is a very simple yet effective way to maximize the collaboration between your projector and the screen surface.

I am not going to promise to do any generic experimenting and in fact it really is only generic and useful as a demonstration so I am more inclined to encourage people to take this sort of iterative approach to determining the optimum sheen for their setup and post as much information as possible to assist anyone else in this method.

If you are going to do some experimenting I would point out that a gallon of paint typically costs the same as two quarts. So it is most cost effective to buy a gallon of the base paint up front rather than start with a quart and have to go back for more paint. In my experience it takes 12 - 15oz of paint to apply two coats to a 2'x4' sample panel. I would suggest that about 5oz. of that is absorbed by the 6mm roller sleeve. A quart is enough to apply 2 coats to a 120" 16:9 screen, if you bag the roller sleeve between coats.

So assume two base coats of just the acrylic paint. Then one coat of paint+poly for each ratio you may try. I would suggest that you will likely use up a quart just laying down the two base coats. You could easily use up a quart trying successive top coats. Then you still need to apply the last top coat.

If you want to dial the screen in for your situation then it would be prudent to get a gallon of latex base paint and you can probably get away with a quart of the Minwax satin polycrylic. Add to that the price of a couple of good quality 6mm nap white lint free roller sleeves. If you wish to try for the smoothest finish possible you could consider the Wganer Control Spray which is around $70 at Lowes or you can achieve some very good results just by rolling since the polyurethane will level the paint out to a surprisingly smooth finish.



Please! If anyone does give this a try then post back how things go, good or bad. By all means poke bud16415 over at AVS or myself, for any further assistance or guidance.

If you really don't want to mess about, then I would suggest that a quart of Behr UPW Flat Enamel 1850 with 1/2 pint (8oz) of Minwax Satin Polycrylic will produce a very nice bright white screen surface.

Plus 8oz. of ==

Hi Tiddler!

Unless you're using New Math, a 4:1 mix would come out to 80%:20%, not the 25% you have written on the test panel.

As you know, I have developed a very light gray reflective paint mix (a true Munsell N9) and posted data on another DIY forum. As soon as I test some panels of several variants of the mix, and get them photographed, I'll post the data here as well. In essence, this mix is slightly darker than Kilz2 while maintaining the white-level of Kilz2 in projected images.

That depends on how you look at it. I tend to think of adding polyurethane and water in the same way. To add 25% water to a paint or mix you would add 1/4 of the amount of paint before the water was added. To add 25% polyurethane would be the same. If you think of the polyurethane more as a paint mix component, which I agree most people would, then you would not say you added 25% polyurethane you would say that the mix had 20% polyurethane or a 4:1 mix of paint + polyurethane.

In the end your way is more clear though and I will keep that in mind in the future.

Very True! I never thought of it that way.

I guess that's why I never liked math too much, two different numbers can mean the same thing!


Only when thinking of it as a paint/poly mix ratio to begin with, as you pointed out.

Same here also on the mathematics tiddler ideas are just dynamite affordable and totally indispensable!

Polycrlic paint that's just great I’ll be looking into that item if its needed for my DIY screen project.

Behr has recently introduce an Interior ULTRA Flat Enamel paint.

For a white screen get the Ultra Pure White #1750.

If it has the same leveling and reflective characteristics as the ULTRA Exterior Flat without the fungicide, then this would make an excellent one can screen paint.

If anyone gives this new paint a try, please let us know how well it levels out and how well it works as a screen paint.