The Coma Berenices star cluster, aka Mel 111, with a smattering of galaxies, taken in the deepening twilight and growing moonlight of a spring evening. The edge-on galaxy NGC 4565 is at left. I shot this as a test of the William Optics RedCat 51mm f/5 astrographic refractor. This was on the iOptron SkyGuider Pro tracker, a popular portable mount to use with the RedCat. I used it unguided for a set of 2 minute exposures. But only 6 of the 12 images taken in quick succession were untrailed enough to be usable in the stack, about typical for shooting with a tracker unguided with focal lengths over 135mm. This is a stack of 6 x 2-minutes at ISO 800 with the Canon EOS Ra. Stacked and blended in Photoshop CC. Taken as the waning gibbous Moon was rising this night on May 8, 2020. The little RedCat astrograph is very sharp to the corners. The field is about 8° by 5.5°.
The Coma Berenices star cluster, aka Melotte 111, at right, with two prominent galaxies at left: NGC 4559 at top left and edge-on NGC 4565 at bottom left. This is a stack of 6 x 8 minute exposures with the SharpStar 76mm apo refractor with the EDPH field flattener for f/4.5 and with the Canon EOS Ra at ISO 800. Diffraction spikes added for effect using Astronomy Tools actions.
Comet Hartley 2 near the Pacman Nebula, NGC 281, in Cassiopeia. Stack of 4 x 6 minute exposures at ISO 1600 with Canon 5D MkII on A&M 105mm apo refractor at f/4.8 with Borg reducer/flattener. Bright star is Alpha Cas, Schedar. Autoguided with Celestron NexGuide autoguider. However, image of comet core is from only one exposure to minimize trailing from this fast-moving comet.
