StarTools

I was able to get out to the club dark site Monday night (having the week off from work). I had my SQM with me for the first time there, the sky measured 21.06 - quite an improvement from the backyard (18.9-ish), though nowhere near "dark" to anyone with access to really good skies. This was also the first time using narrowband there (the 3nm duoband L-Ultimate). I knew I was only going to be able to collect ~3 hours that night (curse you, DST!), and the galaxy targets I would have wanted weren't going to be high enough until at least an hour after astro-dark, so I thought I'd have a go at a challenging HOO target.

The Headphone is a faint planetary nebula (mag 14) - faint enough that it was only discovered from photographic plates in 1939. It is believed to be about 1600 ly away (in Lynx). The mag 16.8 central star is just visible at the center of the nebula. I may someday try for 3 hours from home, to see if the usual "time conversion" is different for narrowband, but my first priority is to hopefully collect some OSC for star color, as the L-Ultimate produces terrible-looking stars that I completely desaturated.

Noise was a struggle, with just 3 hours, so I did use a bit (80% strength) of Dim Small on it. Then I really cheated and opened the .tiff in Siril for a touch of black-point manipulation. So in ST it was Crop, Wipe (NB), Optidev with a tight RoI and lowered Shadow Linearity, Contrast, skip HDR (I played with it, but did not care for the results), Sharp with a mask that included only the nebula and a buffer zone around it and the two lowest scales zeroed out, Color, SS, NR - then the Siril cheat.

SQM 21 isn't dark eh....

What a cool and unusual target. Looking at some references, you even got that little blob of red in the middle.
The Oiii side is pretty noisy. I can't say I'm looking forward to 3 hours from urban skies!

Stars are pretty darn bleached, so much so I thought I accidentally ended up in the PI forums. So agree that some RGB stars will really help.

Simple black point adjustment isn't really cheating, more of a stretching fix! Black clipping is a just a tool anyway, and sometimes perhaps desperately needed.

Mike in Rancho wrote: ↑Sat Mar 16, 2024 6:03 am Stars are pretty darn bleached, so much so I thought I accidentally ended up in the PI forums. So agree that some RGB stars will really help.

I finally got around to adding rgb stars. The rgb stars were so much tighter than the narrowband stars that I ended up using Layer to add the nebula to the star field. Feels a bit cheat-y in my heart but my head tells me it is legit.

Very nice, very nice!
Nice coloring. First picture indeed shows a bit to saturated stars but the second is really nice
These are the targets i wan't to frame with the RC in the future..