Monday, February 4, 2013

50mm Quartz fluorite lens vs enlarger lens for reflected UV photography II

Today again about comparing a quartz fluorite lens with a conventional, but UV capable 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 enlarger lens that will be revealed here later. 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 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!


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