[senkoman]

I am new to this forum and am quite impressed with the vast knowledge base out there. I myself have been designing screens for the motion picture industry for almost twenty years. If you have been to an Imax theatre, a specialty venue theatre, or any world expo, you have seen some of my work.


One item I just have to comment on is all this so called new gray screen technology. Gray screens have been around for over 25 years. Imax has been using this type of surface in it's dome theatres to enhance contrast since I can remember. When the first ever Hughes-JVC came out, we played with gray screens to improve contrast back then. The only problem was the same as it is today. True color rendition as it was meant to be seen is not possible on a gray screen.


Cheating black levels is not a new technology. I do however applaud Stewart for being the first to "market" this technology for use with digital projectors in the home.


Just another note worth mentioning. When the studios mix and play with color balance to come up with their final master print, it is done on a matt white screen. In the future, when the digital projectors can attain the light and contrast (an honest 1000:1 or more) levels equivelent or closer to film........matt white will simply the best option.

 

[ziggyr]

senkoman, welcome to the forum.

Was there ever any gain increasing coatings applied to these gray screens at any time ?.

 

[senkoman]

As a matter of fact we did play with a formulation that gave us a gain of 1.4 and bumped measurable contrast up 18%.


This may sound great at first but everyone has to remember one thing. Any deviation from a matte white screen(or close to it) in colour or gain will always compromise some aspect of the picture in one way or another. In the case as stated above, we had an contrast increasing coating with a healthy gain. In some of todays applications, this may serve a purpose. At the time the trade off was a more narrow viewing angle and the colors were off noticeably.

 

[KBK]

And then, there where the guys using greys in planetarium set-ups, long before any of this.


However, the way the dual-coating sytem came about is an interesing tale....


I also complained that greys would (largely) become irrelevant, and that white would be the screen we would all go back to for maximum energy return. As well, that there is no such thing as a perfect grey, it does not exist.

 

[Geoff Leu]

Interesting post. In flight simulation, we've got spherical wrap around screens, some with enough vertical field of view that they're practically domes. We've run into some technical difficulties with light reflecting all over the place and reducing contrast. Here's a question that perhaps you might have some insight on:


Is there a special low gain paint out there that will help with the problem mentioned above? Currently, the screens are painted with common white latex paint. The contrast really seems to suffer when all the projectors are on, though. What we've tried so far is to cover the walls with black fabric to help minimize reflected light. It helped somewhat... but the colors still look washed out.


Thanks in advance,


Geoff Leu

Systems Engineer

 

[Morbius]

Quote:

Originally posted by Geoff Leu Is there a special low gain paint out there that will help with the problem mentioned above? Currently, the screens are painted with common white latex paint. The contrast really seems to suffer when all the projectors are on, though. What we've tried so far is to cover the walls with black fabric to help minimize reflected light. It helped somewhat... but the colors still look washed out.

Geoff,


Ask the man that posted just ahead of you; Ken Hotte.

http://www.goosystems.com/


Email: [email protected]


Dr. Gregory Greenman

Physicist

 

[Geoff Leu]

Yes, this is exactly the kind of paint I was looking for. Thanks!


-geoff