The Beehive Cluster (M44) is alternatively known as Praesepe (Latin for "manger") and has been known since ancient times when it was described as a little mist or cloud. This cluster is nicely framed by the keystone stars in the constellation Cancer. Three of the four keystone stars are either orange-red or red giants, those being Asellus Australis toward the bottom right, Theta Cancri to the top right, and Eta Cancri toward the upper left. Asellus Borealis on the lower left is a white subgiant star. North is to the left and please click on the preview to see the full-sized image (1600 x 958 pixels).
Taken immediately after the start of astronomical dusk on Wednesday, May 5, 2021 using a Nikon Nikkor AI-S 24mm lens at f/5.6 with a ZWO ASI462MC camera unguided on an Celestron AVX mount. Forty-four subs at 40 seconds each (29m 20s total) with a ZWO luminance filter using a gain of 200 and an offset of 2 from within SharpCap.
Image processing with PixInsight, Affinity Photo, Star Spikes Pro, and Photoshop CC2021.
I was fighting the typical San Diego marine layer clouds ("May Gray") and lost a few subs to clouds before the session was ended by persistent cloud cover at 9:40PM. Taken under red-orange zone light pollution with heavy haze affecting about one third of the subs. Maybe I'll get another 30 minutes tonight before the clouds arrive.
Edited by james7ca, 06 May 2021 - 09:26 AM.