As I was testing a Nikon UV-Nikkor f4.5 105mm, I thought it would be interesting to compare it to my CERCO f4.3 94mm workhorse lens, especially about possible chromatic aberration, sharpness and contrast. Target was a metallic precision ruler, light was sunlight. Only visible light photograhy was done here.
[click on image to see a larger one]
CERCO top, Nikon bottom. Increasing f-stop setting towards the right, starting fully open leftmost.
Both lenses do not show CA. But interesting to note, how much higher the contrast of the UV Nikkor is. The CERCO shows futher decreasing contrast when stopping down (to the right) although flare control was used by using a deep hood against stray light. Both lenses are very sharp, but overall the Nikkor seems to be the clear winner here and it also covers FF sensors, which the CERCO does not do. Both are excellent lenses in terms of sharpness, but contrast and flare always need special attention, especially when using the CERCO multispectral lens.
I have compared quartz fluorite lenses in terms of their transmissions 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