Timber Posted September 2, 2014 Share Posted September 2, 2014 I've 3 enlarger lenses I've tested in UV and sharing if anyone interested. The test is of a very simple situation, a flower (I am afraid to write any specific name because all the botanists here will crucify me if I get it wrong :D j/k) lit by a UV LED light on my desk :) The camera is a Sony NEX-6 and the filterstack used is a Hoya U-360 + Schott BG40. I used an M39 helicoid together with some extension tubes. All shots were made ISO 800, f8 and 1.6". My opinion that the Autocrat is the best in UV but the Nikkor is sharper, especially wide open, where the Autocrat is a little soft. The Rodenstock Rodagon will join my "to be used as decoration" collection, probably I will stick it on one of my Zorkis which does not have a lens :) I hope my wife does not reads this because she was already complaining about having too many lenses (especially about the money I spent on them :P) and if she finds out this one is useless... anyway... back to the topic, here's the result of my today's "been-bored-a-bit-testing" :) http://clancode.hu/!wrx/enlargers.jpg Link to comment
nfoto Posted September 2, 2014 Share Posted September 2, 2014 True botanists are all too aware of the probability of misidentification. They just would help you on and in this case, suggest you have photographed a Hawkweed (maybe Hieracium umbellatum). All three lenses do a credible job of portraying the UV signature of the flower heads. The UV false-colour balance is very cold, though, but that could be your narrow-band UV light source. Link to comment
Andrea B. Posted September 2, 2014 Share Posted September 2, 2014 Thank you for the test, Timber. They all three look like they were capable of recording the UV bullseye. Why didn't you like the Rodagon? We really won't come after you with our torches & pitchforks if you get a flower name wrong!! We'll just try to correct it. B) Do you have any other information about the lenses under test -- like the front filter size, native mount (M39 I'm guessing from the helicoid??) and whether they will focus to infinity with the helicoid in use? Given that they are enlarger lenses, do any of them have an aperture illumination window? Have you performed an in-camera white-balance in your Nex6 under the given filtration? My understanding is that this is possible with the various Nexi. Link to comment
Andrea B. Posted September 2, 2014 Share Posted September 2, 2014 BTW, I am going to move this thread to UV Tests & Techniques. Techniques & Tests rather.Testniques & Techs?Whatever it's called.... B) Link to comment
Timber Posted September 2, 2014 Author Share Posted September 2, 2014 Thank you for the test, Timber. They all three look like they were capable of recording the UV bullseye. Why didn't you like the Rodagon? We really won't come after you with our torches & pitchforks if you get a flower name wrong!! We'll just try to correct it. B) Do you have any other information about the lenses under test -- like the front filter size, native mount (M39 I'm guessing from the helicoid??) and whether they will focus to infinity with the helicoid in use? Given that they are enlarger lenses, do any of them have an aperture illumination window? Have you performed an in-camera white-balance in your Nex6 under the given filtration? My understanding is that this is possible with the various Nexi.The Rodagon has an aperture window which is a source of light leakage. Also I find it's low on contrast and even in visible light test I was not blown away by it's sharpness.All the lenses have M39 mount and on my NEX all can focus to infinity, tomorrow I will try to measure the FFD and do a better test with a flash that gives a bit wider range in UV as I think the LEDs peaking at 390 and not 365 so give a bit more visible than UV... Unfortunately the Autocrat has no filter thread so I am using a wide rubber band on the front of the lens that makes my 40.5->55 step up ring stuck on it so I can use my 55->67 to mount my filters. So far from the 3 I LOVE the Autocrat the most. It's massive, has quite nice weight, beautiful bokeh in VIS as it has 10 blades and always-round aperture. I will receive 2 more "no-name" enlarger lenses and a Nikon EL-Nikkor 50 f2.8 (Newer version) soon so I might add more lenses to this thread :) I am also working on my little Hanimex being fired by the camera somehow (as of now I can only fire it with it's test button with 1/2 shutter speed and good reflexes :D that's how some of my portraits were done). I love to experiment so expect a few more tests from me :) Oh and the flower... I am not a native English speaker so many times I don't know the English name of a plant/flower/weed... but to be honest most of the time I don't even know it's Hungarian name :) Oh and the white balance... I use Adobe Lightroom which is very limited on White Balance settings... so my workflow is I set it to all the way it allows me, exporting it to a 16 bit TIFF where I can fine tune. It worked well in 720nm IR shots so far, but it seems with UV I might need to repeat the TIFF conversion one more time :) Link to comment
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