03 September 2019

Lobster Claw Nebula(Sh2-157)---New Edition 2022---

Sh2-157 in HaRGB

 Sharpless 157, also known as the Lobster Claw Nebula, is a bright emission nebula that lies in the constellation Cassiopeia. It lies just south of the better-known Bubble Nebula (NGC 7635). Within this image of the Lobster Claw are a few other objects. Planetary Nebula PLN 110-0.1 is located near the center of the upper-right quadrant. The bright nebular spot near the center of the image is Lyn's Bright Nebula 537 (LBN537), also known as Sharpless 157a. The small cluster of stars just above the bottom pincer is Markarian 50 and the bright cluster of stars located above the top pincer is open cluster NGC 7510.

Telescope : TS 65Q apo
Mount : Skywatcher AZ-EQ5 GT
Camera : Atik 460 Exm
Guiding : Off-axis with Meade DSI 2
Filters : Astrodon Ha 5nm (29x900sec) all 1x1bin
             RGB Baader (12x300sec) all 1x1bin
Total exposure : 10 hours and 15 minutes from 2 different nights at Grammatiko,Attiki,GR


  1. Do you have the gain/offset you were using on this? This object was brought to my attention today by a fellow imager and I decided to try to go for it. I am running 360s Ha frames at gain 76/offset 50, and it is still very faint. Thanks in advance

    1. Hello Jim and im very sorry for my delayed response. I cant to answer your question because I have the Atik 460ex and the cain/offset in this ccd its auto.The only answer I can give you is the time of single frame in Ha and that was 900sec if I remember correct.I hope I covered you.