ulf Posted January 14, 2018 Share Posted January 14, 2018 Lately I got two Focotar 50/4.5 lenses.One hade a very good UV-performance, the other not.See the red and green graphs in post #22 here:http://www.ultraviol...ce/page__st__20 Those lenses opened for an interesting spectrographic comparison.What happens when the transmission is combined with one of our most common UV-pass filter Baader U? The measurement of my Baader U below is reasonably correct both for transmission and wavelengths.That I cannot achieve with lenses in my measurement setup.Instead I tried to match the long wave slopes of the lens-filter combinations to the filters spectrogram.Because of this the Lens-filter transmissions are showed a bit too high in amplitude. The result: The difference is interesting, but in then our camera sensors also lose their sensitivity in the short wavelength end, making the difference a little bit less important. Link to comment
Cadmium Posted January 14, 2018 Share Posted January 14, 2018 Nice comparison! I missed that you had added a Focotar-2 to your test collection. Link to comment
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