Wednesday, October 1, 2008

Lens Comparison: UV Nikkor 105mm, COSI 105mm, B&L 9"

Today I got an old lens, which was made many years ago by famous lens maker Bausch & Lomb, Rochester NY. It is a golden color single coated, heavy and well made f4.5 9" lens which attracted me, since it was made to record images emitted by a P-16 phosphor screen. Nothing special actually, but P-16 radiates at about max. 380nm, so now you know what attracted me most...

I ran a quick test using my "standard test subject", a roof of the neighbours house against the Coastal Optics Micro Apo 105mm and the Nikon UV Nikkor 105mm. The B&L lens results are shown on the right side of the comparison images. The B&L images have been scaled down to match the shorter focal length of the other two lenses. These are 100% center crops. The Baader U-filter (310 - 390nm) was used for the reflected UV shots. [click on image gets you a larger image]

Here the results in visible light for the UV Nikkor (left):




and for the Coastal Optics 105mm (left):




Here the results in reflected UV light using the Baader U-Filter (310 - 390nm) for the UV Nikkor (left):




and for the Coastal Optics 105mm (left):




So now it is up to you to understand my surprise, how amazingly sharp this B&L lens is....

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

Allium (Onion) in UV

So this is about onions in UV light. These have very cute ball-shaped flowers and I wondered how these would look like in UV "light". The petals seem to have quite some strong UV reflectance to attract pollinators.

So have a look, left is the visual image, middle the reflected UV image and right the image with UV remapped into the visual as blue [click on image gets you a larger image]:




And this one in a bit higher resolution:




So I hope you like these as much as I do....

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