Friday, December 22, 2017

#122 - Wednesday, December 20, 2017 - Darn, Foiled Again!

This time, I got out of the house on time (almost) - I scarfed down a homemade egg & sausage sandwich, threw my gear in the car, and got out to the observatory a little before 6 PM.  The sky was still darkening, but a few stars were popping out.  I cautiously entered the Asian beetle-infected dome and started getting setup.

Things went fairly smoothly this time - I cranked down hard on the screw holding the drawtube of the focuser in place using my Leatherman, since it tends to slip, took my time centering the Pacman Nebula (NGC 281) in the view and double-checking, and then I started acquiring 10-minute subframes with my red filter in place.  I got 20 wonderful luminance frames back in November, so now I just needed RGB color frames.  I wanted to pack up at midnight, so with my remaining time, I calculated I could get 9x600s subs for each color channel, plus some extra time built in for changing filters and fixing guiding problems.  Guiding got off to a bit of a rocky start (I don't think this scope is balanced for having a heavy camera dangling off the back, so it's got quite a bit of backlash that PHD has to push through first), but then settled down nicely to about 1 arcsec error or less.  The sky looked great.

The club's 140mm Vixen neo-achromat refractor on its Losmandy Gemini mount, with my borrowed SBIG ST-8300M CCD camera attached.

After setting up the CCD camera inside the memorial dome, I next set up my Nikon D5300 on my Vixen Polarie star tracker (see more about it in this post) and aimed it at Orion.  It hadn't quite cleared the trees yet, but I went ahead and started the run and figured I would just delete the ones with the trees still visible later.  Since I don't have the polar alignment module for it, I could only get about 60 seconds of exposure time at 95mm focal length pointing southeast in order to get minimal trailing (there was still some trailing though).  It came out quite nicely.
Date: 20 December 2017
Object: Orion's Belt
Camera: Nikon D5300
Telescope: 50-200mm lens at 95mm, f/4.5
Mount: Vixen Polarie
Subframes: 103x60s (1h43m), ISO-1600
Darks: 60
Biases: 0
Flats: 0
Temperature: 29F

If you go check it out on AstroBin, you can see what all is in this image, including four nebulae and of course, the three stars that make up Orion's Belt!

I went out and checked my gear periodically, rotated the scope, and then switched from the red to the green filter (I have a manual filter wheel that is a lot better than my old one now!).  Around 10:30, I went outside to check again...and clouds had rolled in! D:  I stopped taking images and went back inside and waited about 20 minutes, but it wasn't looking like it was going to clear up anytime soon.  All my forecasts had promised me no clouds until at least midnight.  Oh well...

On the bright side, I did get a solid set of red frames on the Pacman Nebula, and I got this nice widefield of Orion.  

Someday, I'll get a complete CCD images of the Pacman Nebula!

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