I am testing to see if what is said about 9 hours being minimal time for a truly deep sky image. Collecting 9 hours in Syracuse is at least a 3 night proposition but I was able to keep just for minutes shy of 10 hours for this image. There is a definite improvement over the 6.5 hour image in brightness of the galaxies and smoothness in the background. Here is the final image and links to the previous images. The differences are subtle. At a quick glance, I don’t really see much difference in the three pictures. But when […]
Astrophotography
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For astrophotography of deep space objects like galaxies and nebulae, I would say little is to be gained from better than 2 arc-sec per pixel. Even at 2 arc seconds other factors play a significant role in useful resolution. How stable are your skies? What size aperture is your scope. How good is your mount over the integration period? How good is your alignment? 2 arc seconds is a rule of thumb. It is doubtful that around Syracuse that the sky is better than 2 arc-sec and you can’t correct for it – without adaptive optics. A 4″ aperture scope […]
About a year ago, I wondered what magnification I was getting with my astrophotography set up. The best answer came from an article on Cloudy Nights. That article said that there really isn’t any answer to the question of magnification in photographs, but you might approximate the magnification by considering your eye as the eyepiece at the main focal plane of your telescope. The human eye has a focal length of 22 mm, so the magnification your eye would see can be calculated by dividing the focal length of the telescope in millimeters by 22 millimeters. Using that algorithm gave […]
There was a little bit of “Smoke Gets In Your Eyes” last night at the DHO, but it was much drier, so no constant use of the hair dryer to keep everything from getting soaked. Overall, the seeing went from baleful red Saturn and Jupiter, to fair conditions as the smoke cleared somewhat. I started with something nearly straight overhead to help reduce the effects of the smoke and started over with M13 so I could change the composition to include the galaxy NCG 6207 (bottom left in the picture). That means you also have to include the bright red […]