Tuesday, January 8, 2019

Russian Telegoir f2.8 / 200mm prototype lens for reflected ultraviolet (UV) photography

Today tests shots in reflected ultraviolet photography of an Oncostele orchid with an older Russian multicoated Telegoir f2.8/200mm prototype lens, designed in 1975 and built 1991. UV filter used was a Schott UG1 + BG38 filter stack. All shots were done at f5.6. Light source used was a modified Xenon flash as well as a Nichia high power UV LED emitting at 365nm.

[click on image to see a larger one]

Schott UG1+BG38 filter stack with Xenon flash:
 

Schott UG1+BG38 filter stack with UV LED:
 

Schott UG1+BG38 filter stack with UV LED whitebalanced:
 

Visible light image:
 

VIS and UV image side-side:
 

This Telegoir lens has despite its MC coating a surprisingly high UV transmission and I will try it out outside, once weather is permitting. A further feature seems to be that this lens has a very small focus shift!

I have shown more about this flower in UV HERE

Outdoor shots in UV and IR using this lens 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