8mm Forum: Projection lens and screen size

This is topic Projection lens and screen size in forum 8mm Forum at 8mm Forum.

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Posted by Rui Luis (Member # 3867) on October 24, 2015, 04:12 PM:

Hello, i like to know if exist some kind of way or formula to calculate the maximum size of projection screen can each specific lens do.

For example what the maximum size of screen can do a f: 1.4 F: 25-50 mm lens?

Thanks

Posted by Dominique De Bast (Member # 3798) on October 24, 2015, 05:30 PM:

Luis, I'm not sure I understood your question : do you want to know the sizes you can get from your lens according to the projector/screen distance (the aperture, as far as I know is not involved) or do you want to know the theorical limit ? In the first case, there are tables that give you theses sizes, in the second case, I have no idea if there is a way to calculate that.

Posted by Rui Luis (Member # 3867) on October 24, 2015, 05:32 PM:

Hi Dominique, thanks! is the second, where i can get that tables?

Thanks

Posted by Dominique De Bast (Member # 3798) on October 24, 2015, 05:40 PM:

You can find them in projectors manuals or in books for cine amateurs. I have a small table in front of me but should have others. For example, with a 25 mm super 8 lens, you get a 0,42 x 0,31 picture for a 2 meters distance, a 1,27 X 0,95 one for 6 meters and 2,56 X 1,92 for 12 meters.

Posted by Rui Luis (Member # 3867) on October 25, 2015, 05:24 PM:

Hello Dominique!

I dint remember to see in the manuals, i already have the tables in the manual of Elmo 1200HD.

Thanks!!

Posted by Dominique De Bast (Member # 3798) on October 25, 2015, 05:51 PM:

Hope it helps you :-)

Posted by Rui Luis (Member # 3867) on October 25, 2015, 05:59 PM:

YEs i hope! There will be Film projections in a building roof in Lisbon!! [Smile]

Posted by Dominique De Bast (Member # 3798) on October 25, 2015, 06:04 PM:

Great new !

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