The evening of Jul 25, 2020 was supposed to be clouded out. It was at first, but for a short time, a sucker hole opened and I was able to get a batch of sub-images of Comet NEOWISE. The total was 57×4 sec shots, but only 47 of those would stack correctly, so a little over 3 minutes of exposure. Too bad it wasn’t totally clear. Oh well, it is what it is.
I guess I am lucky to even get images. July is the worst month for an evening comet here along the Gulf coast. We have thunderstorms galore in the afternoons and left-overs of them for hours afterwards and into the evenings.
I did do another rendition of the 47×4 sec data set. This time I aligned on the comet when stacking and it helped it come out better than before. Surprising how much it moved in the short exposure run vs the background stars, which you can see by how long the stars are elongated in this version and the comet is not:
Comet Neowise in between clouds, Jul 23, 2020. It was probably the best night weather wise since Comet Neowise moved to the evening skies, but still too cloudy to bring out my bigger scope. I used a Canon T3 on a tripod with a Sigma 28-70 Zoom for this session.
The top image is stacked with more adaptive noise reduction/rejection and the bottom was a straight additive stack to max out the dimmest parts. All subs were dark and offset calibrated.
Not too bad for being in a Bortle 7 Red Zone and using only an IDAS-LPS filter. But, I need to get to a dark sky location (and some better weather) before this thing passes me by! LoL! Soon, hopefully.
Clear skies, but muggy and lots of muck to shoot through with it that low. It was the clearest morning so far since the comet became visible. That’s a dirt pile in the foreground, btw and not a mountain. LoL!
Below is an image that is a reprocess job on the data with a different color balance, slightly more sub-images and tighter cropping. I also did dark and offset calibration to try and reduce noise.
I was hoping it would come out better than the first one, but since conditions were sub-par to begin with, I guess I will just have to wait until it gets in the evening skies to get a better shot. Oh, well…
Friday night, Jun 19th, 2020 was warm and muggy and clouds persisted till after 9:00 PM. It was predicted to clear, so I went to bed early and woke up just before 2:00 AM and setup my scope then. It was clear, but the transparency was poor and the humidity was still high.
I managed to get a decent amount of data on two objects, and I also peeked at 2 or 3 other things in between. M22, the globular cluster in the first image, was a secondary target and I really wanted to get the Omega Nebula and the Trifid Nebula nearby. My narrow window to image them was so small, however. Trees and streetlights were in the way. By the time I was ready to shoot, that area had moved out of position.
I had imaged M22 a few times, but with other scopes. I took all the data I had on it and recombined it to produce the 2nd image above. It is data from an 8″ Schmidt-Newt and a 6″ Schmidt-Newt, along with the data from the first image above.
The Ring Nebula was a quick peek that turned into a usable image. The full size image is a crop at 100% resolution of the central area. I was hoping to pick up that galaxy that is nearby to the Ring, but 48×15 sec sub-images wasn’t enough to bring it out.
However, I did have a stack of 34×30 sec sub-images taken in March that I blended this night’s data with and now you can see it, just barely, above and slightly left of the ring. Check it out:
It looks like I need to get out of the big city to get the summertime nebulae targets like Omega and the Trifid. Late June and early July sometimes has clear skies and hopefully I’ll be lucky and get to a dark sky site before too long.
I think the last time I shot this was in 2014. This would be the first time imaging it with my new QHY183c camera. Not too bad for only 1.8 hours of exposure. Plus, it was very short 15 second sub-images, which kept the stars nice and tight.
Images of Comets, Nebulae, Galaxies and Star Clusters