Iris Nebula, NGC7023 by Anne van Houwelingen
Imaging Location: My backyard (orange zone)
Telescope: Ritchey-Cassegrain (prime focus). F=1000mm F/D=3.0
Camera: Starlight Xpress SXVR-26C OSC
Integration time: 15 hrs over 8 nights (90x600s). Heavily dithered.
Pre-processing: APP
Average stack, quality weight, discard worst 5%, LN sigma clip kappa 3 – 1 iterations
Post Processing APP + Photoshop
APP: Calibrate background, remove light pollution, calibrate star colors on area’s without nebulosity, HSL to eliminate green pixels and reduce color noise of background, DDP (20%BG, 3 sigma, 2,.5% Base), Highlight protection.
Photoshop: Various targeted contrast stretches, noise reduction, selective sharpening, star shrinking etc.
About the object:
Diffuse reflection nebula in a molecular cloud complex. In its center a young pre-main sequence star whose stellar wind and UV radiation have carved out the cave like structure and lights up the walls.