Monday, April 17, 2017

An Open Cluster Stack

Those who know about my enjoyment of astronomy, also know I enjoy meteor photography.  I set my camera gear up for all showers, including minor ones, to get that perfect meteor.  I have yet to capture that “Great Nighttime Meteor,” but I keep shooting and trying for that one shot.

A while back, I purchased a Tolkina wide-angle zoom mainly to use for meteor photography.  However, I also use it for wide area shooting of the night sky. 

Recently, I used it (combined with my Canon EOS 60D) to shoot a dozen images of Melotte 111, or Collinder 256.  To many, the naked eye open cluster is called the Coma Berenices Cluster.  The cluster is located below the bend in handle of the Big Dipper and about three times the distance the top of the bowl covers…if that makes sense.

Saturday evening proved to be one of the few clear nights I have experienced here lately, so I took the recently acquired Celestron SkyMaster 15x70 binoculars outside and pointed towards the cluster.  From what I have read, the cluster covers about 7.5 degrees in the sky.  Unfortunately, the SkyMaster binoculars have a field of view of 4.5 degrees.  Wanting to see the entire cluster in one swell swoop, I decided it was time to break out the Canon.

At the time I decided to photograph the cluster, it had moved to directly overhead and getting my tripod to point straight up takes a lot of leg adjusting and balance checking to get things working together.  The problem is my tripod is designed mostly for video work and not well suited for working straight up.  Once I found the balance point, I took a couple of test shots, saw that the cluster was most likely in the view and after setting the lens to 14mm, shot a dozen 10-second exposures.

Since I have yet to have good luck stacking images, I wanted to practice with these photos using DeepSkyStacker.  I have other stacking programs, but they are the ones I have used in the past with non-impressive results.  For the most part, it is the alignment of the images which have been the problem in the past.

After transferring the images to my computer, I started DSS on the working computer and opened the User’s Manual for DSS on the laptop for reference.  I really didn’t need to read much to figure out how to use DSS.  It is rather straight forward if the person doesn’t plan to do a lot of manipulation of the images prior to and during the stacking process.  I just wanted to see a good stack with stars aligned well.

And that is what I got.  The image below is the results.  My only concern is in the stacking process, a lot of the stars visible in the original images are not in the final product.  I should probably read the manual.




The cluster is located in the lower left area of the image about a quarter of the way from the left edge.  It is a small grouping of stars in the image, but through the binoculars, it is spectacular, even if I cannot see the entire cluster.

One other note of interest to no one in particular…today I began receiving items I ordered which I plan to use during the “Great American Eclipse” on Aug. 21.  Soon as the days clear here in the Pacific Northwest, I will accustom myself to their usage.


My next trip to the stars will most likely be early morning on April 22.  You guessed it…the Lyrid Meteor Shower.  Although the shower officially began April 16, and will end on April 25, the peak of the shower is predicted to be around 3 a.m. April 22.  My camera is ready to go if the weather cooperates.

No comments:

Post a Comment