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The diffraction pattern is due to the combination of the Fraunhofer diffraction of the circular aperture, the the blades of the iris at the f-stop, f, and the slits of the Bathinov pattern. The ...
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The number of line pairs across the diameter of the Basinov mask needs to match the intended aperture to be tested. A 50 mm lens at f/1.8 has an effective aperture diameter of 28mm. This is the ...
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30 minutes after I wanted a Bathinov mask I had one in a 52 mm threaded mount. The same evening I was able to try it out. I have not tried it, but I should.
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It is not that hard to make one yourself. It took 30 minutes. after finding the instructions http://www.deepskywatch.com/Articles/make-bahtinov-mask.html . Print the 62 mm pattern on paper and ...
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Very nice. At f/2? From a dark site? It will be interesting to see how the galaxies pop out, once the you get the lens in focus, At f/2 there is no room for error. Does the lens improve at f/2.8? hha
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Nikon 28mm f2.8E. I have used it on my D7200 and my Z6,
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I am not sure what you are telling me, since I am not a collector. For taking star picture this 1957 Topcor 135mm/f3.5 at f/4 is better than my Nikkor 135mm f/3.5 Q at f5.6 from 1975. But my ...
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Do you have samples at f/2.5? You left out the photon noise. You increase the signal (2.5/2)^2=1.6, but the noise increases at the square root, so the net gain is only 25%., All of you suggestion ...
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I included photos further down. Apparently this lens was made to fit on the Leica knockoffs produced win Japan.
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Thanks. This was a very helpful reference, which show the lens. It was apparently made for a the Leica copies. It appears to be 1956 vintage. Optically (for star pictures) it is much better than ...
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mapachebasura If the Nikon Z6 does not allow you to put your lens close enough, nothing will. Get a cheap Leica screw mount to Z6 adapter (Fotasy US $18) , bore out the Leica part and insert you lens.
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ffereres: I have taken many star pictures with a Nikkor 10P mmP f/2.5 at f/4, Excellent lens, but i wanted more star-like patters, not round stars. I have a Nikkor 135 mm f/3.5 Q, but the blue ...
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Interesting. Thanks for all the history lessons. Here are two pictures The picture makes it look like the lens has a barrel bulge in the middle. Not true. I got too close Here it is from the front. ...
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Thanks for the information. I checked the mount. It is not a detachable adapter from one mount to another but attached with 3 screws to a brass ring which ends in the Leica screw mount.
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I found this Topor 135mm f/3.5 (chrome barrel) with a Leica screw mount in my collection of old Leica gear. My guess is that the Lens is from the 1970s, At that time TOPOR was a top brand. So I ...
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All the previous responses are good. The best one is to start with a photographic lens and a simple sky tracker. Here is what you can get from a Nikon Z6 with a 40 year old Nikkor 105mmP f/2.5 at ...
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At iso200 you may get a little digitization noise, at least that is what I get with my D7200 and Z6, so I stay at iso400. I find the Bortle scale not very useful in estimating how much you may gain ...
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Very nice result from a backyard. What iso did you use? Your 130mm f=650 mm system is f/5. How big was the sky background (histogram level))? From this and f/5 you can estimate how much a good ...
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Total messages |
613 |
Threads started |
48 |
Last post |
4 days ago |
Total reviews |
13 |
Last review |
Sep 11, 2013 |
Photos uploaded |
6 |
Last upload |
Jan 27, 2014 |
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