Comet NEOWISE (C/2020 F3) over the still waters this night of Crawling Lake in southern Alberta. This was early in the evening with the sky still brightly coloured with twilight. The comet was in the southern part of Ursa Major between the pairs of stars called Tania and Talitha. The clouds that were present nicely framed the scene and reflected in the water as well. The comet was too high to be visible as a reflection at this time. The main image content is a single untracked exposure of 20 seconds at f/2.8 and ISO 640 with the 35mm Canon lens and Canon 6D MkII. The distant clouds, horizon, and water in the distance and in the immedate foregound without stars is from an average stack of 6 exposures, all at the above settings, to smooth noise. I shot this from Crawling Lake in southern Alberta on a near perfect night.
Comet NEOWISE (C/2020 F3) in a telephoto lens close-up on July 19, 2020, showing the straight blue ion tail and the curving whitish-yellow dust tail. Even the ion tail was visible in binoculars and traceable out for 12° or so, or two binocular fields. A bit of cyan colour is visible around the head of the comet. The ninth magnitude galaxy NGC 2841 is visible to the right of the comet. This is a median stack of four 1.5-minute successive exposures with the Canon EOS Ra at ISO 1600 and Canon L-series 135mm lens at f/2.8, on the iOptron SkyGuider Pro tracker but unguided. Stacked and aligned automatically in Photoshop with the Scripts>Statistics function. I focused the lens with a Bahtinov mask which does help nail focus. I didn’t stack any more images to keep the relative motion of the comet against the stars to a minimum, to minimize blurring of the subtle structural detail in the ion tail. Residual twilight adds the sky colour. I applied gradient masks to help remove the sky gradients toward the bottom (horizon). Median stacking mode used to eliminate some satellite trails. A high pass filter helped bring out the ion tail details. Other than that I did not apply any local adjustments to the ion tail to accentuate its brightness relative to the dust tail. But as always, the long exposure of a camera reveals more than the eye can see. That’s the point of astrophotography. This was on a night when the sky cleared after a day of storms and rain, so the air was very damp but quite transparent. The comet was low in the northwest with some light cloud still wafting through adding some subtle red patches. I shot this from home in Alberta.
