PK094+27.1 - Dim Planetary Nebula in Draco (and Quasar)
PK094+27.1 - Dim Planetary Nebula in Draco (and Quasar)
PK094+27.1 - Dim Planetary Nebula in Draco (and Quasar)
It wasn't until I was processing the pic that I found out there's a quasar right next to the nebula. KUV 18217+6419 is one of the brightest quasars, and at ~3.7 Billion light years away, it's the most distant thing I've ever photographed. Captured over a bunch of nights from October through December, 2023 from a Bortle 9 zone.
Places where I host my other images:
Acquisition: 63 hours 18 minutes (Camera at unity gain, -15°C)
Capture Software:
PixInsight processing:
Preprocessing
Narrowband Linear:
duplicated each image and removed stars via StarXterminator. Ran DBE with a shitload of points to generate background model. model subtracted from original pic using the following PixelMath (math courtesy of /u/jimmythechicken1)
$T * med(model) / model
RGB linear
Nonlinear:
R = iif(Ha > .15, Ha, (Ha.8)+(Oiii.2))
G = iif(Ha > 0.5, 1-(1-Oiii)(1-(Ha-0.5)), Oiii (Ha+0.5))
B = iif(Oiii > .1, Oiii, (Ha.3)+(Oiii.2))
"unstretched" both images with histogramtransformation midtones set to 0.9999
pixelmath to just add those two images together
histogramtransformation to un-relinearize them by setting midtones to 0.0001