Thursday, January 30, 2014

IC 443 Jellyfish Nebula in Jan 2014

Via Flickr:
IC 443 AKA the Jellyfish Nebula and region as seen from Montebello OSP on Sunday January 26, 2014. I wanted to return to this area after a year away from it with one night of good data.

What's interesting here is the reflection from Propus that appears at the top of the image. Chasing these reflections is a challenge and I've traced it back to the Feathertouch focuser. There are a lot of shiny bits in the drawtube that allow just enough light to shine when a bright object is off to the side. Flocking the drawtube helps considerably. Still, there's opportunity to have some glinting.

This is a stack of 14 subexposures for 4 horus and 40 minutes of integration. Had to refocus once through the session at the meridian flip. Have taken to focusing 1/3 from the center and this helps flatness considerably.

Calibrated in Maxim, stacked in DSS, processing in PI. Cropped off ragged edges, DBE, Masked Stretch script, Histogram stretch, unsharp mask on the lightest regions, curves applied to bring up the bright and drive the dim lower.