Lover, likewise not trying to sound like an ass. For the benefit of others reading this thread I was mainly correcting the misleading statement that grey non-ALR screens "kill the whites and devour brightness yet they wash out just as easily as a white screen in low levels of ambient light." That's only true if your projector isn't adjusted to or isn't capable of the correct lumen output to properly illuminate the screen.
I appreciate the fact that you have bought and sold a warehouse full of AV equipment and have strong opinions based on your personal experience and preferences. But for expertise on screen performance I rely more on what has been shared by
who has decades of experience as Stewart Filmscreen's chief technical officer. From everything I've ever seen stated by Mr. Stewart, <1.0 gain matte grey screens have fewer issues than any ALR screen. In fact the only issue a <1.0 gain matte grey screen has is that it requires more lumens to properly illuminate. ALR screens on the other hand have a variety of issues, the most obvious of which is reduced viewing cone.
As you noted in your last post, no screen is "best" for all environments and user preferences. In some cases an ALR screen might be more appropriate and in some cases a <1.0 gain matte grey screen might be better. But using a <1.0 gain matte grey screen is certainly not "living in the past." Just a few years ago the lowest gain matte grey screens offered by companies like Da-Lite and Draper were 0.8 gain. Today both offer darker matte grey screens with as low as 0.6 gain. This makes sense as projectors in general continue to get both brighter and more accurate.
Anyway it's always good to hear multiple opinions and compare the opinions to the science. Speaking of science, Don Stewart knows more about screen science than the rest of us combined. So quoting him from a post he made here two years ago is a good read for anyone who doubts the validity of <1.0 gain matte grey screens:
Originally Posted by Don Stewart
Bud, you may appreciate this story because you are a proponent of low gain Lambertion gray screens. We at Stewart have had the honer to design, engineer and manufacture all of the Disney 360 Circle Vision theater screens and framing systems which are located at the Disney theme parks throughout the World. (See photo below) When we built the first system, we assembled it on a sound stage at the Disney Studios in Burbank. This nine segmented screen system was to be used for post production and sound editing only. Anyway, the screens that Disney specified and ordered for the mock up theater were Snomatte 100 lamberlion white diffusion screens. Well... you can guess what happened when they fired up the nine projectors for the first time. The theater looked like the inside of your refrigerator when you open its door. The 360 degree screen vista washed out the adjacent screens and cross reflected to the opposing screens on the other side of the theater. It was a mess and the studio brass were not to happy as a lot of money had already been spent on shooting the raw film footage. After some head scratching by both the Disney and Stewart teams the idea came up to engineer and produce a front projection ND gray screen. What initiated the ideal was Stewart and other screen manufactures had been producing dark gray contrast enhancing ND rear projection screens for decades. Why not do the same for front projection? So after a few weeks of intense R&D Disney approved a very dark gray, 0.4 gain FP screen surface. Since the 0.4 gain screens were not as efficient as the 1.0 Snowmatte 100 screens, Disney had to increase the lamp output by 250%. But they did not care as the project's success was riding on the gray screens. In fact, Disney engineers have a saying called the bigger hammer theory. " If the hammer in hand does work, then break out a bigger hammer" or something like that. In this case they broke out the sledge hammer. Also, the nine gray screens had to be lambertion with no gain coatings because with 200 or so viewers in the theater, each of the nine screens had to distribute the exact same luminance to each viewer no matter where they were positioned in the theater. To the best of my knowledge, these were the vary first commercial gray screens. It was around 1979 and I was a very young man at the time.