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Your D5600a has the extended red response. This probably explains why M57 with your D5600a has a little reddish cast compared to the more blue with my stock D7200. Cheers, hha
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Hi: Mario. Thanks for the screenshot. I rotated and scaled it to approximately match my image. Yes. M57 is resolved with your Sigma 105mm at f/2. Very impressive. cropped from 4000x6000 D7200, ...
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Mario: Nice lens and lots of stars. Two days ago I took images of the Lyrae constellation with a 135mm lens, but I posted only a small crop (at full resolution with a D7200) of the Vega and ...
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When stopped down a little, all lenses show a diffraction pattern (sun star) around bright stars. For some lenses the pattern is ugly, for other it can have an artistically pleasing effect. Shown ...
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Thanks for the picture. It appears to cover a 3 degree area. To analyze your "No CA" comment I did some manipulations in PS. On the left is a picture of eps10/20 Lyrae cropped from your picture ...
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Maybe a 200 or 300 mm lens would be a good starter for clusters and some of the bigger galaxies. The longer and bigger lenses on your list require a lot of experience and $$$. hha
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David: Interesting writeup. I have accidentally taken and processed series of defocused images. All but the faintest stars tend to have magenta or cyan haloes, depending on which side the focus ...
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Yes, this 50 year old lens Nikkor 200mm Q f/4 lens, used at f/4. It has only four elements, and was corrected for only two colors, i.e. achromat. The challenge I proposed to the readers is to take ...
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Tristimulus: Notice I said "colorful stars" not "star colors". Since we are not doing any science with these pictures, a little color thrown in, even if an artifact of the lens, does not hurt. You ...
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I got tired of looking at colorful pictures of emission nebulae, so here is a colorful star pictyre. On the left is a 300x600 crop centered on eps01/eps02 Lyrae, taken with a 50 year old Nikkor ...
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The Earth rotates 360 degree in 24 hours = 15 degree/hour = 15 arcsec/sec.
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Obviously, if your polar alignment is not perfect, you will get trails. How long a trail will you accept in your 1 minute exposure? How are you going to process the data afterwards? Here is my ...
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Very nice result of M13. What caused you to limit the exposure to 120 sec per shot? hha
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For a 24 Mp camera the rule of 500 is way to slow. The first picture, which shows the moon emerging from the hillside at about 12 degree elevation, was taken from a fixed tripod with the 200mm ...
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For those who got clouded out Nikkor 200mmQ f5.6 iso200 10 sec StarTracker. Enjoy. hha
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I am routinely getting 4 hours (240 shots at 1 minute each) from a 2280 mAhr ENEL 15C battery with my Z6 and be down to one bar on the battery meter, You can scale it from there. A 5000 mAhr 7V ...
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This time I centered on NGC4649 and missed the Markarian chain. I did a quick slice across the the SN and NGC4649. The SN as of 4/30/2022 22:00 PDST is 2.5 times brighter than the nucleus! Cheers hha
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Andresch: A 400 mm should work, obviously not as good as your 6"/f5. (f=750mm). On Saturday night I took 4 hours (240x1minute) of images of the Virgo Cluster with my Nikkor 180mm ED f2.8 at f/4 , ...
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Very impressive picture. I tried from my backyard (Bortke 7) with a 180mm f/2.8 ED, but the sky was too hazy. In the 1990's there was a group at the UC Berkley Astronomy department, which hunted ...
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Excellent for a first attempt, with darks, lights and flats in 50 x 4 = 200 seconds. A Bortle 2 sky helps. You used a Sony 85mm f/1.8 lens. In 4 seconds you will get 60" of sky rotation. Barely ...
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Total messages |
709 |
Threads started |
55 |
Last post |
2 days ago |
Total reviews |
13 |
Last review |
Sep 11, 2013 |
Photos uploaded |
6 |
Last upload |
Jan 27, 2014 |
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