On Mar 12, 8:41 pm, King Sardon wrote:
I'm considering building a camera obscura to project prints. The
prints would have a max. dimension of 20 inches. Have any of you guys
built one of these? Any suggestions?

The most critical component is probably the lens. It should probably
have a focal length of 500-800 mm and a diameter of at least 3 inches.
Where would I get a lens like this? Edmunds comes up blank.

I would also need a first-surface mirror unless I have the print
parallel to the projection screen.

Suggestions appreciated.

KS



Large format camera lenses (5 x 7 and 8 x 10) would work.
Unfortunately these are VERY expensive. Look for surplus copy machine
lenses. Try googling something like "surplus" and lenses or optics.
There are several places that sell surplus lenses, but I cannot think
of name of them now.

Also old aerial cameras used such focal lengths, and I have seen
surplus aerial camera lenses at surplus sites- bought a couple a
number of years ago.