The large star cluster in Coma Berenices known officially as Melotte 111, at right, with two of the most prominent galaxies in Coma at left: NGC 4559 at top and the Needle Galaxy, NGC 4565, at bottom. Several other fainter galaxies are in the field, including NGC 4494 between the Needle Galaxy and the star cluster, but looking very star-like at this image scale. I shot this April 11, 2021 on a fairly clear night as a test of the new SharpStar 94mm EDPH refractor telescope and its matching field flattener/reducer. A bit of passing haze added a touch of star glows. There is a version of this same field shot a week earlier in hazy skies with much fuzzier stars. This is a stack of 20 x 6-minute exposures at ISO 800 with the Canon EOS Ra, autoguided on the Astro-Physics Mach 1 mount with the Lacerta MGEN3 stand-alone autoguided set to dither 5 pixels between each exposure. No dark frames or LENR were applied. The field of view is about 3.3° x 5°.
The Coma Berenices star cluster, aka Mel 111, with a smattering of galaxies, taken under dark skies on 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 (which provides a focal lengthof 250mm). 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. Of the 20 exposures, 12 were relatively untrailed and so were selected for stacking for this image. This is a stack of 12 x 2-minutes at ISO 1250 with the Canon EOS Ra. Stacked and blended in Photoshop CC. The little RedCat astrograph is very sharp to the corners. The field is about 8° by 5.5°.
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°.
