Here’s 3.3 hrs of data on two NGC objects, 6939 and 6946, that happen to be side-by-side in the sky. Conditions were decent and I was able to get plenty of sub-images.
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Here’s one you don’t see too often. A large spiral galaxy that happens to be dimmed by dust in our galaxy. If it were not for that dimming, this object would be one of the brighter DSO’s in the sky. It is still the 3rd largest galaxy visible to us, behind M33 and M31, the Andromeda Galaxy.
The Gamma Cass area with the, “Ghost Nebula” (IC63) was an appropriate target for this time of year with Halloween just around the corner. This was actually just a test run for how well ISO 6400 would work with 80-100 sub-images. Click the image for an enlargement or click here to see the full size version.
The obligatory Helix Nebula photo for 2014. This was taken in the early evening hours of October 24th, 2014.
Update October 20, 2014: The above image is an update with more time added. Compare it to the image below which was made with only 20 minutes of data shot at ISO 6400 (20×60 sec sub-images.) I took an additional 30 minutes of 3 minute sub-images at ISO 1600 and added it in, so the combined total is 50 minutes.
Well, the big comet encounter of the year took place tonight, Oct 19, 2014 and Mars and Comet Siding Spring (C/2013 A1) both survived. LoL. Seriously, it was a very close encounter if you had darkness when it was closest. Here in southern Louisiana, it took place during daylight, so I had to catch it after closest approach as C/2013 A1 was bidding Mars farewell.
I had a strange night with some issues, but I managed to get some decent data and also lucked out with some good weather for this event. This image is from the first set of images I took and it is a composite of comet-only processed and star background processed image stacks. The comet moved a good distance in the twenty-five minutes it took to get the sub-frames, so I had to isolate it with different alignment and stacking techniques than I use for normal deep-sky images.
Here’s another ISO 6400 test image and I think it came out pretty well. Temps were only in the mid to low 60’s, so noise was an issue. However, the test reveals that with enough sub-images, the noise can be smoothed out. I did notice that there was a remnant pattern noise that I see when guiding was off and tracking in a certain direction. Dithering during guiding would help for that, but I did not set that option during my imaging session. For sure I’ll try that next time.
Well, I finally managed to catch that small comet that is about to side-swipe Mars. It was a last minute effort and I caught the comet late and a little too close to the horizon. It was so low, that I had to throw out the last six sub-images because they were way too red. At that point, the comet was only 2 degrees above the horizon. That’s probably the lowest angle I ever tried to image something.
The actual close approach to Mars will occur on October 19th, 2014. Hopefully, I’ll get a chance to shoot it again at that time. It’s a little runt comet, but at least it is newsworthy. lol
For this image, I had to travel a few miles from home to find a western horizon free of obstructions, since from my backyard it is impossible to see. I ended up staying there most of the night since the sky was so nice.