5 sessions. Actually there were 6, but the second-to-last of these sessions, in which I wanted to test Narrowband-O, didn’t work due to a technical misunderstanding, or rather was manually aborted by me.
Messier 101, the Pinwheel Galaxy, had been a long-sought target with my new cooled system. There were 3 imaging sessions with the UHC filter on the RGB sensor and 2 additional sessions with my new ultra-narrowband H-alpha filter. The first light, so to speak, of this accessory.
The imaging experiences with narrowband and ultra-narrowband filters deserve a separate account in a future article.
Overall, I was incredibly delighted by this unusually long stretch of good weather and was able to make excellent use of it.
I think this fifth photo of the Pinwheel Galaxy by me definitely has the greatest depth and quality.
High-resolution on Astrobin:
The annotated image:
Session Details:
| Telescope | Vixen VC200L |
| Focal Length | 1800mm |
| Erecting Lense | internal |
| Camera | ToupTek SkyEye24AC ToupTek SkyEye62AM |
| Filter | Baader UHC-L CMOS Optimized 50.4mm Baader H-alpha Ultra-Narrowband (3,5nm) CMOS Optimized 50.4mm |
| Mount | Skywatcher HEQ5 Pro, Belt and Hypertuned |
| Astro-Computer | ToupTek Stellavita |
| Guiding Equipment | APM 240mm |
| Guiding Camera | QHY 462C |
| Photography Date | 04/21/2026 (UHC-L) 04/22/2026 (UHC-L) 04/23/2026 (UHC-L) 04/24/2026 (H-alpha) 04/26/2026 (H-alpha) |
| Exposure-Time Lights | UHC-L: 165x300s H-alpha: 95x300s |
| Correction frames | FLATS, DARKS |
| Sensitivity | GAIN 100, Offset 125 |
| Processing Date | 05/07/2026 |
| Software Stack | PixInsight |
| Capture Place | Koblenz, Germany |
