I made this as a trial, and it works perfectly. But I need to make another one,
about half the focal length, because (using a factor of .299), I calculate this
"lens" is like a 35mm focal length when used on a regular 35mm camera. I think if I
reduce the box focal length to around 75mm, I'll have a 22mm equivalent
- nice and wide for a 4x5. That will also reduce the weight of this 'puppy'.