JW> Yes expensive for what they are, but I guess there's no point in buying a
JW> cheap one. I was thinking of making my own using the front element from a
JW> 50mm f/1.7 M (mechanically damaged) and suitable tubing, but I'm not sure
that
JW> the magnification would be sufficient.
50mm lens is quite ok as a loupe. It allows you to see the whole
negate/slide at once, unlike shorter lenses. Taking the front element?
Why? You would probably end with extremely low power loupe with a lot
of spherical and chromatic aberations. Just use the whole lens -
that's what it was corrected for, after all! camera lenses make highly
corrected loupes.
However, you need at least 1.4 aperture to be able to see a whole 35mm
frame at once. With 1.7, you won't be able to see it all.
Good light!
fra
