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Showing results for tags 'telescope'.
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Like a scene from a movie, the control room of the groundbreaking Soviet-era Orgov Radio-Optical Telescope (ROT-54) in remote part of Armenia stands quiet against the pastel sun lit room. M10-P Reporter & Nokton 351.4 MAP edition.
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I am always thinking about new ways to use my Q ... The other day, I was mousing around the Leica Rumors site, and I accidentally came across an article written on Feb. 27 of 2017 about adding a Konica Minolta ACT-100 1.5x telephoto converter lens to the Leica Q. It caught my attention for several reasons - first, of course, it would be great to have some additional focal length flexibility on the Q (rather than just cropping!), second, because that particular teleconverter has a 49mm screw thread, which allows it to be directly attached to the front of the Q lens, third, because it has some serious glass - it weighs 1 lb. 2 oz, the front lens is 3 1/4 in. in diameter, and according to Konica Minolta it has 5 elements in 3 groups! Plus, I was able to purchase one in absolutely pristine condition on eBay for about $45.00! So when I got the lens, I tested it, and it screwed on perfectly - confirming a standard 49mm thread! But when I turned on the camera, even with the giant objective lens, there was major vignetting - I had to set the camera to 50mm crop just to get rid of the very dark edges. And worse, when I tried some photos, there was only a small sweet spot in the center third of the 50mm crop which had good optical quality - beyond that everything was smeared. I have attached a resized 50-mm crop of a landscape, plus the same landscape through the A-100. It may be harder to tell where the quality starts to deteriorate in these drastically-resized photos, but it is easy to see that there is still vignetting in the A-100 photo, and a closer inspection will show the smearing outside the sweet spot. Regretfully, I have to conclude that for an additional lens which weighs almost as much as the entire Q, the usable area of the enlarged image is just too small (sad face), but my next step is going to be attaching the Q to my real telescope, to see how that works Stay tuned - and let me know if you have any better results using other teleconverters! Sincerely, Richard