Image of the Shrimp (or Dolphin) Nebula (Sh2-188) captured on the nights of December 20, 2023, January 4&26, and February 3, 2024. Sh2-188 is a planetary nebula in Cassiopeia.
Imaged with a William Optics GT81 at F4.7 (382 mm focal length) using Flat6A II field flattener/0.8x reducer, Optolong LeNhance dual narrowband and UVIR cut filters, and ZWO ASI 533MC Pro.
Total integration time of ~9 hours:
LENH NB filter = 101 subs at Gain = 100 with an exposure time of 300 seconds
UVIR cut filter = 39 subs at Gain = 100 with an exposure time of 60 seconds
Processing:
- All images pre-processed using Pixinsight's weighted batch pre-processing script (WBPP) to perform calibration, debayering, registration, local normalization, and integration (1x drizzle). Initial post-processing in Pixinsight: gradient correction process, spectrophotometric color calibration, blur x terminator, and noise x terminator.
- RGB stars image processing (UVIR cut filter data): Color saturation boost and stretch using Bill Blanshan's unlinked histogram transformation process. Generated stars only version using StarXterminator.
- Starless image processing (narrowband data): Generated starless version using StarXterminator. Extracted Red/Green/Blue channel data. Used Red image for H-alpha data and average of Green&Blue images for OIII data. Generated HOO image using SHO-AIP script. Stretched using Bill Blanshan's unlinked histogram transformation process (background=0.10). Narrowband normalization process on HOO image: Mode 1 used to generate SHO palette style image and Mode 2 used to generate HOO palette image. Final color saturation boost using color saturation process.
- Final image generated by combining OSC RGB stars only and narrowband starless images using Pixelmath process. Additional post-processing: EZ HDR script, AdvSharpen script, and AstroDepth Image Enhancer script by Seti Astro.
Original version: Sh2-188, HOO palette
Rev B: Sh2-188, HOO palette, starless
Rev C: Sh2-188, SHO palette
Rev D: Sh2-188, SHO palette, starless
Rev E: Sh2-188, LENH filter R channel data, starless
Rev F: Sh2-188, LENH filter averaged G/B channel data, starless
Reg G: Sh2-188, UVIRC data
Comments