Today again about comparing a quartz fluorite lens with a conventional, but UV capable D.O. Industries enlarger lens. I have done a similar comparison previously here. I'm using a beautiful yellow/red Phalaenopsis flower, for that as well as my "work horse" UV filter, the Baader-U filter. Lenses used are a Hamamatsu f3.5/50mm quartz fluorite lens as well as a 4.5/50mm D.O. Industries enlarger lens. Light source was an UV enhanced Xenon flash. All shots done at f8.
[click on image to see a larger one]
Visible light image for comparison:
1) Quartz Fluorite lens:
"standard" UV image using Baader-U filter:
2) Enlarger lens:
"standard" UV image using Baader-U filter:
UV - VIS differential:
It gets pretty obvious that this very affordable D.O. Industries enlarger lens reaches quite close to the quartz fluorite lens, yet can't quite beat it in terms of sharpness + contrast. But it is astonishingly close. Also its focus shift is relatively small, as the differential image clearly shows. Quite a nice lens!
I have written about that enlarger lens before HERE
Stay tuned, more will follow on that fascinating subject...
More info on this very interesting field may be found on my site http://www.pbase.com/kds315/uv_photos