Capture summary
Nebula in Cassiopeia
9 days / Moon 59%
Chroma H-alpha 5nm Bandpass 36 mm, Chroma OIII 5nm Bandpass 36 mm, Chroma SII 5nm Bandpass 36 mm
Autumn target / wide composition
- H-alpha 10h 120 x 300s / 4 days in Dec 2022 / Moon 90%
- SII 7h 30m 90 x 300s / 3 days / Moon 46%
- OIII 10h 25m 125 x 300s / 4 days / Moon 37%
- Totals 27h 55m 9 days / Moon 59%
The Lobster Claw Nebula is a sprawling Sharpless emission region in Cassiopeia. It does not present itself as a simple, isolated object; the appeal is in the overlapping shells, ridges, and wispy edges spread across the star field.
The narrowband palette helps organize that complexity. Hydrogen, oxygen, and sulfur data give the frame its layered look, with warmer emission wrapping around cooler pockets of structure.
Acquisition Data
Technical capture details from the public AstroBin record for this image. View on AstroBin.
- H-alpha: 120 x 300s, 10h, 4 days in Dec 2022, Moon 90%
- SII: 90 x 300s, 7h 30m, 3 days, Moon 46%
- OIII: 125 x 300s, 10h 25m, 4 days, Moon 37%
- Totals: 27h 55m, 9 days, Moon 59%
Equipment and Software
- Telescope: Explore Scientific ED APO 127mm f/7.5 FCD-100 CF HEX
- Camera: ZWO ASI2600MM Pro
- Mount: iOptron CEM60
- Filters: Chroma H-alpha 5nm Bandpass 36 mm, Chroma OIII 5nm Bandpass 36 mm, Chroma SII 5nm Bandpass 36 mm
- Software: Adobe Photoshop, Sequence Generator Pro, PixInsight
- Guiding camera: ZWO ASI290MM Mini
Target Planner
Nebula in Cassiopeia; best planned for September through November from New Jersey.
Autumn is a strong window for Cepheus, Cassiopeia, Andromeda, and late Cygnus fields.
Assumes a New Jersey backyard horizon and evening imaging.
Emission nebulae are good candidates for narrowband filters; reflection nebulae prefer darker skies.
Sh2-157 is listed here in Cassiopeia.
Current frame: Narrowband / Ha, OIII, SII.
Calculating target altitude and moon context.
Use the full planner to enter a ZIP code, choose a date, and compare the target from your sky.
Based on the current time.
Green marks usable dark-sky altitude.
Next upper transit.
Approximate horizon crossing.
Moon phase and altitude.
