December’s weather has been horrible. For the last 10 days it has been wet and cold and too cloudy to shoot any images of any comets. Finally, it cleared enough to get out. Unfortunately, while it was clear initially, clouds moved in before I could get a good amount of sub-images of Comet Lovejoy. I did get 21 of them, so at least I did not scratch.
Below is the star streaks version of the data, with a few clouds for good measure. LoL. 🙂
Comet Lovejoy composite image taken with a Canon 200mm telephoto lens. I shot 40×30 sec sub-images at ISO 3200 and stacked them. The first image of the set was used as the background base image. I then took the stack of subs and combined them with the base to show the tail better. To me, this shows how the comet sort of looked in binoculars as it was rising from behind the trees.
I also did a star-streaks stack that shows the extent of the tail better than the image above. I did very little post-processing on it, since that just took away from the raw feel of the image:
With all the hype about Comet ISON going on over the past 2 days, we still have a very nice comet to look at that is putting on just as good a show – Comet Lovejoy. Here’s how it looked the morning after Thanksgiving Day with a 200mm F/2.8 telephoto lens mounted on a simple equatorial tracking mount. I used 2 light pollution filters for this since I had to shoot towards a very bright LP dome from a metropolitan area to my northeast. It was a test and it seems to have worked beautifully. Next time, I’ll try this with the camera on my bigger mount and track the comet with much longer exposures.
Here’s about 10.75 minutes worth of sub-images stacked to show the extent of Comet ISON’s tail. Mount troubles and twilight limited my exposures, but at least I didn’t scratch. Probably the last image pre-perihelion, since the weather will not be good for imaging again until next week and ISON will be too low to see by that time.
This morning (Thursday, Nov 14, 2013) I observed ISON and imaged it. Boy, what a difference from yesterdays observations. It has shot up immensely in brightness since yesterday and is now naked eye. Its so bright you can see an intense teal-green color in binoculars.
I managed to get about 28×30 sec images of the comet rising from behind the trees in my backyard. I combined most of them into an animated GIF image above. It shows the comet from about the start of astronomical twilight until the sky got too bright and the comet was moving back into some tree branches (about 5:11 A.M. local time until 5:33 A.M. local time.)
My image above is a composite of a single 30 second sub-frame for the background with an 18×30 sec stack of the comet blended in. I was using a Canon 200mm F/2.8 lens and had the camera (a modified Canon T3) by itself on a CG3 clone mount with a rudimentary clock drive. There was no guiding.
BTW, the sub-image with the meteor is presently being used by Sky & Telescope on their website for a couple of stories on Comet ISON:
High altitude clouds from the subtropical jet stream barely gave me a break to image Lovejoy on the morning of November 14, 2013. I was shooting most of the sub-images through the clouds and consequently, didn’t go as deep as I had planned. I had to throw out more than half of the sub-images, unfortunately.
Probably my best Comet Lovejoy image to date. Lots of subs and setting up especially for shooting it helped quite a bit. I missed shooting ISON because of setting up for Lovejoy unfortunately. Oh, well…
After shooting Comet Lovejoy, I had just enough time to shoot 4 to 8 sub-images of Comet ISON. By that time, the sky was getting bright with the approaching sunrise and these images were all too blue. But, I decided to try and put together a display picture anyway since it had been since Nov 4th that I last shot some images of it.
I shot this right after shooting 18 sub-images of Comet ISON. Twilight was already approaching really fast and by the time I got 7 images taken, the sky was too blue to continue. So, this version is lightened up somewhat to bring out the faint details that I couldn’t get because I didn’t get enough sub-images. It shows the comet well enough, at least.
I was experimenting with high ISO settings and short exposures for this impromptu imaging session of Comet ISON. I went with 1 minute at ISO 3200, which is equivalent to 4 minutes at ISO 800, the ISO setting I was using for most of my other ISON images. That is double what I was using before. Yes, its noisier, but tolerable in the cool 47 degree temps I had that morning.
Also, this is the full field of my imaging rig. The only cropping done was to remove places where the sub-images did not overlap. I wanted to demonstrate how large the comet is getting.
Images of Comets, Nebulae, Galaxies and Star Clusters