[typek]

Hey guys...

I usually frequent the REP over on PSW, but I had a question that I think would be best answered over in these parts... I am an AV technician at a hotel, and I have always been a little cloudy on my projection chops - I often just throw up projectors and wing it... Wondering if you guys could help me clear up a few things, or point me in the right direction.


(Lens size) * (screen width) = projector distance away from screen

So if its a .8 lens * 10ft = 8ft away (ideal distance)?


Is this true?
Also... Here is a question I have been wondering.

How is my 9x12 Fast fold screen's dimensions directly related to a certain aspect ratio? Is a 9x12 screen "tailored" for a certain aspect ratio?

Can you guys recommend any good AV books that cover this stuff? I am graduating with a degree in Audio Engineering, and unfortunately we have not covered any of this in school. I want to be just as knowledgeable with projection as I am with Audio signal flow.

[Harpmaker]

I can't answer your first question myself, but here are two sites that might help.

Projector.com Projection Lenses Questions and Answers with formulae

Controlling Projector Image Size and Throw Ratio >> Big Screen Center

Assuming that 9x12 is the dimension of the screen surface, this would be a 4:3 ratio screen. 12/9=1.33333 and 4/3=1.33333. This would be the "native" aspect ratio. Other aspect ratio images could be shown on this screen, but they would be "letterboxed" and have black bars above and below the image.

I don't know of any books on this subject, but a LOT of info is available via the internet, just use your favorite search engine and dig a bit.