This is the fairly bright emission nebula NGC 281 in Cassiopeia near the star Alpha Cassiopeiae, or Schedir, at right. NGC 281 is also known as the Pacman Nebula, an obviously modern name but quickly becoming dated! This is a stack of 8 x 8-minute exposures with no filter, blended with 5 x 12-minute exposures with an Astronomik CLS broadband nebula filter, all with the Canon EOS Ra, at 1600 for the unfiltered shots and ISO 2500 for the filterered shots due to the filter factor. All were through the venerable Astro-Physics Traveler 105mm apo refractor at f/6. And on the AP Mach1 mount. Clouds prevented more filtered shots. Guiding was with the new Lacerta MGEN3 stand-alone autoguider, using its function of also controlling the camera shutter and performing “dithering” to shift each image by a few pixels at random so thermal noise averages out when the images are stacked and aligned on the stars. For the test, I did not use Long Exposure Noise Reduction or any dark frames, to test the effectiveness of the dithering in averaging out the thernal nouse. It seemed to work fine! And the MGEN guided very accurately. In this case, all stacking and alignment was with Photoshop 2020. The Lacerta MGEN3 is made in Hungary and sold thru 365Astronomy in the U.K. where I bought it from.
This wide-field image frames the prominent emission nebula IC 1396, at left, and the faint arcs of Sharpless 2-129 at right, in southern Cepheus. IC 1396 contains the dark Elephant Trunk Nebula at about the 3 o’clock position in the nebula. At the top edge of the nebula is the orange giant star Mu Cephei, aka Herschel’s Garnet Star. The dark nebula at top left is Barnard 169-70-71. The dark nebulas at the bottom of IC 1396 are B160, B162 and the snake-like B365. A small blue reflection nebula below and left of the Sharpless complex is VandenBurgh 140. This is a blend of filtered and unfiltered shots, all with the William Optics RedCat 51mm astrographic refractor at its native f/5 and with the Canon EOS Ra: 6 x 8-minutes at ISO 1600 without the filter and 4 x 12-minutes at ISO 5000 with the Optolong L-Enhance filter, which reduces light by about 2 to 3 f-stops but really makes the H-alpha nebulas stand out. All stacked, aligned and blended in Photoshop. LENR employed on all frames on this warm summer night to ensure the most accurate dark frame subtraction of thermal noise but at the cost of doubling the capture time.
This area in Cygnus that contains the circular Cocoon Nebula, aka IC 5146, located at the end of the long dark nebula called the Dark Cigar but officially is Barnard 168. The nebulas are flanked by two open star clusters: NGC 7209 at far left just over the border in Lacerta, and Messier 39 at far right. NGC 7209 barely stands out amid the rich starfield here, just below an orange star, while M39 is bright but sparse at right. The clusters and dark nebula stand out well in binoculars but the Cocoon Nebula is a challenge to see in telescopes. This is a stack of 6 x 6-minute exposures with the William Optics RedCat 51mm astrographic refractor at f/5 and the Canon EOS Ra at ISO 800 with LENR on as it was the warmest night of the summer, August 18, 2020. Aligned, stacked and median combined in Photoshop to eliminate some satellite trails. Autoguided with the ZWO ASIAir and ASI120MM guide camera with the RedCat on the Astro-Physics Mach1 mount. No filters employed here.
