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:
This Week’s Sky at a Glance – Some night sky sights for November 15 – 23
Not sure how long they will include the image on their website, but its given me lots of exposure. 🙂
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…
Below is the Star Streaks version.
Continue reading Comet Lovejoy (C/2013 R1) on November 8, 2013
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.
Below, I have included the star-streaks version:
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.
I shot comet ISON on the morning of November 3rd, 2013. I devoted most of the morning to Comet Lovejoy, but there was still enough time to get nearly 30 good sub-images of this object which is enough to make a pretty decent image. Clicking the picture brings up a half-of-full-size enlargement. Click here to see the image at the camera’s full resolution. The “star-streaks” version is below:
Comet Lovejoy is dominating the comet fiesta that is now occurring in our skies. It is the brightest and the biggest, by far! My most recent images show a 70 arc-minute tail that is best seen in the negative inset view.
I was looking at some unprocessed data recently (Oct 5, 2014) and found this set of 40 sub-images taken at ISO 6400. It was a batch of 60 second subs, so only 40 minutes worth of integration. It came out surprisingly well for just 40 minutes. I’ll have to try some more with that setting and see if I can get some dimmer nebulae.