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.
Comet NEOWISE (C/2020 F3) over a ripening canola field near home in southern Alberta, on the night of July 15-16, 2020. Light pollution from a nearby gas plant reflecting off low clouds and a rain shower adds the yellow at right. This is a blend of a stack of three 2-minute exposures at ISO 1600 and f/5 to smooth noise, provide depth of field, and bring out the colours of the canola, blended with a single short 15-second exposure of the sky at f/2.8 and ISO 3200, all with the 50mm Sigma lens and Canon 6D MkII camera.
Comet NEOWISE (C/2020 F3) over a ripening canola field near home in southern Alberta, on the night of July 15-16, 2020. Light pollution from a nearby gas plant reflecting off low clouds and a rain shower adds the yellow at right. This is a blend of a stack of seven exposures to smooth noise, blended with a single exposure of the sky, all at 30 seconds at f/2 and ISO 1600, all with the 20mm Sigma lens adapted to the Canon EOS Ra camera.
