Now this will be a rather lengthy entry I presume, so be forewarned! Why you might ask? Well today I got a request and di a comparative shootout of various lenses for UV, using that Rudbeckia fulgida flower as a target, ca. 80mm (3.1") in diameter. The Baader U-filter was used, as well as Xenon lighting and UV LED lighting (365nm).
The candidates were the classic UV Nikkor 105mm, the Coastal Optics Micro Apo 105mm, the UV Rodagon 60mm (making up the group of the most expensive ones), then the EL Nikkor 3.5/63mm enlarger lens and my calibrated lenses for UV in 50mm, 90mm and 135mm focal length (X50, X90, X135).
Here now the results, and as usual here, a click on a picture opens up a large version of it.
UV Nikkor 105mm:
Visual shot:
UV shot:
Coastal Optics Micro Apo 105mm:
Visual shot:
UV shot:
UV Rodagon 60mm:
Visual shot:
UV shot:
EL Nikkor 63mm:
Visual shot:
UV shot:
X50 calibrated lens for UV 50mm:
Visual shot:
UV shot:
X90 calibrated lens for UV 90mm:
Visual shot:
UV shot:
X135 calibrated lens for UV 135mm:
Visual shot:
UV shot:
And now here a few days later a rare find, the results using an UV Rodagon 150mm. The flower has aged of course...
UV Rodagon 150mm:
Visual shot:
UV shot:
But now you're up to you to interpret....
[Just some hints: be careful when comparing the images, since the working distance had to be very different due to the different focal lengths used to achieve about the same magnification. So you will notice, that although the same aperture f8 was used, the depth of focus is different. This is because of the changed angle of view, and has nothing to do with a lens being more or less sharp.]
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
