Object: NGC 7331
Constellation: Pegasus
Date: 21 October 2008
Equipment: SXV-H9, Vixen VC200L (f9, f.l. 1800mm)
Subframes: 30 x 60s 2x2 binned subframes, stacked in AIP4Win.
A crystal clear, moon free evening allowed me to attempt imaging this fuzzy in Pegasus. A slim lens shaped glow with a bright central star-like centre was clearly visible through a 25mm eyepiece on the VC200L.
Swopping the eyepiece for the SXV-H9, I thought I'd have a quick play at checking the scope's collimation using the free trial download of CCDWare's CCD Inspector. It's dead easy to use and I was pleasantly surprised to find that the VC200L appeared to be spot-on. Not sure I'm advanced enough yet to want to fork out for a "keeper", though...
Getting a polar alignment that was accurate enough to avoid tracking errors at an 18oomm focal length was a bit more of a challenge. The GPDX mount's polar alignment scope usually puts me pretty close, but that isn't good enough for imaging with the VMC, and I have to resort to repeatedly downloading 30 second frames and iteratively adjusting the mount alignment until no trailing is evident and the stars stay in exactly the same position for a few minutes. It took me about 40 minutes to get an alignment I was happy with.
Running the periodic error correction then seemed to remove the last few jitters from the otherwise pretty smooth drive. I had planned to take at least a hundred 60 second subs, and then try my luck with some longer ones afterwards. I watched the first few download and then left the equipment to do its stuff.
Mistake. I had clumsily let the lead to the RA drive trail over the counterweight shaft, and as the mount tracked, it pulled the lead tight and then out of the motor! I returned after a couple hours to find I had only got about 30 subs of the 100 I wanted, and as it was now past midnight and I had to work the next day, I gave imaging up as a bad job. A stack of what I got is what you see, a lot noisier than I would have liked, but still showing a moderate amount of detail (click to enlarge).
Ace astroimager Rob Gendler brings out slightly more detail in his effort here, showing structure in the associated "Deer Lick" group of galaxies (also nicknamed "the Fleas", so I gather) that show up as mere fuzzy blobs on my more humble effort.
Frustrations aside, the night really was too clear to miss out on though, so I dropped the 25mm eyepiece back in and spent 30 minutes or so getting some knock-out views of open clusters M52, NGC 884 & 869 (the Double Cluster, each of which fitted nicely into the field of view) and NGC 457 (the Phi Cas cluster, which I had never seen before and which almost appeared three dimensional it was so bright) before finally calling it a night.
It's not all about gadgets...
Work and sleep - the twin curses of amateur astronomers everywhere.
Type: Galaxy
Distance: 50 million light yearsConstellation: Pegasus
Date: 21 October 2008
Equipment: SXV-H9, Vixen VC200L (f9, f.l. 1800mm)
Subframes: 30 x 60s 2x2 binned subframes, stacked in AIP4Win.
A crystal clear, moon free evening allowed me to attempt imaging this fuzzy in Pegasus. A slim lens shaped glow with a bright central star-like centre was clearly visible through a 25mm eyepiece on the VC200L.
Swopping the eyepiece for the SXV-H9, I thought I'd have a quick play at checking the scope's collimation using the free trial download of CCDWare's CCD Inspector. It's dead easy to use and I was pleasantly surprised to find that the VC200L appeared to be spot-on. Not sure I'm advanced enough yet to want to fork out for a "keeper", though...
Getting a polar alignment that was accurate enough to avoid tracking errors at an 18oomm focal length was a bit more of a challenge. The GPDX mount's polar alignment scope usually puts me pretty close, but that isn't good enough for imaging with the VMC, and I have to resort to repeatedly downloading 30 second frames and iteratively adjusting the mount alignment until no trailing is evident and the stars stay in exactly the same position for a few minutes. It took me about 40 minutes to get an alignment I was happy with.
Running the periodic error correction then seemed to remove the last few jitters from the otherwise pretty smooth drive. I had planned to take at least a hundred 60 second subs, and then try my luck with some longer ones afterwards. I watched the first few download and then left the equipment to do its stuff.
Mistake. I had clumsily let the lead to the RA drive trail over the counterweight shaft, and as the mount tracked, it pulled the lead tight and then out of the motor! I returned after a couple hours to find I had only got about 30 subs of the 100 I wanted, and as it was now past midnight and I had to work the next day, I gave imaging up as a bad job. A stack of what I got is what you see, a lot noisier than I would have liked, but still showing a moderate amount of detail (click to enlarge).
Ace astroimager Rob Gendler brings out slightly more detail in his effort here, showing structure in the associated "Deer Lick" group of galaxies (also nicknamed "the Fleas", so I gather) that show up as mere fuzzy blobs on my more humble effort.
Frustrations aside, the night really was too clear to miss out on though, so I dropped the 25mm eyepiece back in and spent 30 minutes or so getting some knock-out views of open clusters M52, NGC 884 & 869 (the Double Cluster, each of which fitted nicely into the field of view) and NGC 457 (the Phi Cas cluster, which I had never seen before and which almost appeared three dimensional it was so bright) before finally calling it a night.
It's not all about gadgets...
Work and sleep - the twin curses of amateur astronomers everywhere.
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