c-mount lenses for reflected UV photography

Today about a find I made a while ago, when I wondered if those usually small c-mount lenses (originally used for video and cine) would be suitable for reflected UV photography. And indeed out of the many I have for normal photography, just a few turned out to be useful. I'm using a yellow/red Phalaenopsis flower for that and my "work horse" UV filter, the Baader-U filter. Light source was an UV enhanced Xenon flash. All shots were done at f8 and are presented side-a-side for easier comparison.

[click on image to see a larger one]

50mm - Visible and UV image using Baader-U filter (approx. 320-395nm, effective peak approx. 375nm):
 

40mm - Visible and UV image using Baader-U filter (approx. 320-395nm, effective peak approx. 375nm):
 

40mm w. 1.4x Barlow lens - Visible and UV image using Baader-U filter (approx. 320-395nm, effective peak approx. 375nm):
 

That 50mm lens has 1.0% focus shift, whereas the 40mm (w/o) Barlow has 0.5%, with Barlow 1.0%. Of course those lenses do not reach that deep into UV, but seemingly deep enough to make them a suitable alternative and a small and lightweight one!


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