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.
Open Cluster NGC 6939 & Galaxy NGC 6946
Category Archives: Star Clusters
Two Globular Clusters and a Comet
Two globular clusters in Aquila and a very tiny comet are visible in this image. I only wanted to check the size of Comet Jaques on this night, since I missed imaging it when it was at it’s best. I regret that I did not get a chance to shoot it back then, but at least I finally got to see it.
Comet Siding Spring Meets Mars
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.
The Crescent Nebula Area – Mosaic
11×480″ ISO800 (5.21 hrs.) Data acquired on Oct 17, 2014, Nov 2, 2013, Nov 6 & 7, 2010 and Oct 1, 2007.
11×480″ ISO800 (5.21 hrs.) Data acquired on Oct 17, 2014, Nov 2, 2013, Nov 6 & 7, 2010 and Oct 1, 2007.
A mosaic of the Crescent Nebula area. Exposures from 4 different years were used. The base image was acquired on Nov 2, 2013 and was 40x60sec ISO 6400. I imaged it again on October 17, 2014 with 77 images and added that into the mix. Two nights of imaging in Nov 2010 of 9×720″ ISO400, 11×480″ ISO800 sub-images were also added in (for a total of 5.21 hours integration time.) Finally, data from an image of just the Crescent Nebula itself, taken with my SN-8 telescope was used and it was made with 57×180″ ISO 1600 sub-images taken on Oct 1, 2007.
I used RegiStar to manipulate the data. The beauty of software like RegiStar is that it can combine data taken years apart. In this case, over 7 years. I was able to take the nebulosity caught with a high ISO stack of sub-images, but with a noisy background and combine it with stacks of subs taken at lower ISO values which had a much smoother background. The stacked mosaic-like result let me bring out more of the dim nebulosity that pervades the Crescent Nebula area and keep the noise at bay, somewhat. A little more detail in the Crescent itself was enhanced with data from my larger, 8″ scope.
I present a regular version and an enhanced, lighter version that was generated from the data in the first image with Starizona’s Levelizer plug-in for PS.
The Pleiades (Combined Data)
This image of the Pleiades was a combination of data from October 2013 and October of 2011. I sized it to be used as a screen background for my current monitor.
The “Coathanger” Asterism
Here’s an area I’ve always wanted to shoot simply because I like seeing this in my binoculars. 🙂
M38, NGC 1907 and IC 417
This is a busy area in the Auriga constellation. M38 is an open cluster at the top of the frame. Beneath that is NGC 1907, another open cluster. To the right side is a faint nebula listed as LBN794 in Cartes du Ciel. At the bottom of the frame another patch of nebula known as IC 417/LBN804.
Edit: I managed to add 40×30 sec @ ISO 6400 sub-images to this and the above image has been updated. Below is the original details and image:
The Pleiades October 2013 Version
Here’s the obligatory M45 image for the month of October, 2013. I shot this while waiting for other objects to get into position.
Antares and Two Globular Clusters in Scorpius
M4 and NGC 6144 are two globular cluster near the bright star, Antares in Scorpius. I shot this while waiting for Comet Pan-STARRS to come into view.
M41 Open Cluster in Canis Major
An easy to find open cluster that lies just below Sirius, the brightest star in our skies here in the northern hemisphere. I had just setup and needed something to test the rig and make sure everything was working. M41 was convenient so I shot 10 x 3 minute sub-images and combined those to get this final image. There was lots of moonlight and LP, so open and globular cluster shooting is about all you can do in such conditions.