So today it is about a lens I had laying around for many years, intended to use for reflected ultraviolet photography, as it is a simple achromat from what I know, the NOVOFLEX T-NOFLEXAR f5.6/400mm.
To find out if there is a chance to get it to work, best aside from just trying out, to chech with a suitable spectrometer if there is some useful UV transmission - and this will be shown here. As a comparison, I will use two other lenses, both well known to work in UV, the Kuribayashi f3.5/35mm and the NOFLEXAR f3.5/35mm lens (also made by NOVOFLEX).
[click on image to see a larger one]
Now this transmission spectra clearly shows, that although the T-Noflexar 400mm cannot beat the Kuribayashi 35mm lens, it is very close to the Noflexar 35mm lens transmission, which is considered quite useful for reflected UV photography. It delivers about 67% transmission at 365nm, the Kuribayashi however has 78% there.
Remark: the 100% line reflects the transmission of a white SPECTRALON (R) reflection standard with 99% reflection in the 300-700nm region, so this result should be a true representation of the lens transmission.
I will shoot a few test images in visible light and UV, weather permitting. It is dull grey winter weather now, so that might be in coming spring...
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