Messier 13 - The Great Globular Cluster - First Light for My Askar FRA400 Platform
Date: June 3, 2021
Cosgrove’s Cosmos Catalog ➤#0071
Messier 13 - The Great Globular Cluster - and the first light for the Askar FRA400 Platform (click to enlarge)
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About the Target
Messier 13 is the grandest globular cluster in our skies and, as such, is extremely well know. It is a bright object and therefore an excellent target for a first imaging attempt on a new platform.
Here, for your convenience, is a summary from Wikipedia :
M13 was discovered by Edmond Halley in 1714 and cataloged by Charles Messier on June 1, 1764, into his list of objects not to mistake for comets; Messier's list, including Messier 13, eventually became known as the Messier Catalog.…..
About 145 light-years in diameter, M13 is composed of several hundred thousand stars, the brightest of which is a red giant, the variable star V11, also known as V1554 Herculis, with an apparent visual magnitude of 11.95. M13 is 22,200–25,000 light-years away from Earth.
Single stars in this globular cluster were first resolved in 1779. Compared to the stars in the neighborhood of the Sun, the stars of the M13 population are more than a hundred times denser. They are so densely packed together that they sometimes collide and produce new stars. The newly formed young stars, so-called "blue stragglers," are particularly interesting to astronomers.
The Annotated Image
Annotated image created with Pixinsight’s Imagesolver and AnnotateImage scripts.
The Location in the Sky
IAU/Sky & Telescope Constellation Map of Hercules, with M13 indicated by the yellow arrow.
The Project
I have recently shared my efforts to pull together a new lightweight, portable rig - but at that time, I had NOT yet tested it and confirmed that it would perform to my satisfaction.
Of course, once you get new gear, the clouds roll in and shut everything down for a 100-mile radius (sorry, my fellow Astro fiends!) - and this was true in my case as well - except that this occurred in a callous way…. We have had a string of really nice days, but once it began to get dark, the clouds would roll in and shut me down for the evening.
This changed on the first of June. I waited for the clouds - but they never came! So I finally had an opportunity to shake down the system and to test things out.
There is a lot of steps to do when first using a new rig{
Level the mount… Check!
Set zero position and locked the mount's axes…. Check!
Plug in all of the cables…. Check!
Hook up my Polar Alignment camera… Check!
Run Ipolar software and do the Polar Alignment… Check!
Run my Guiding Software and set it up….
Build a dark library
establish a center of rotation,
run a dark calibration
Run Guiding Assistant… Check
Watch the guiding for a while… Check!
Fire up Sequence Generator Pro and Select the FPA Hardware Profile…. Check!
Connect all devices and allow the camera to start cooling until it gets to the target temperature…. Check!
Test camera capture with one frame… Check!
Manual Rough Focus….Check!
Test Auto-Focus…. Check!
Test Object Slewing and Centering (thus testing Plate-solving as well)… Check!
Us the Mosaic Planning tool to set up a test sequence on M13… Check!
Run test sequence….Check
Use my newly built Flat Cal light source to capture calibration Flats… Check!
Capture Darks and Flat Dark cal frames…. Check!
Verify Meridian Flips are handled right.. Check!
All-in-all, it was a very productive night!
Attached is my very first image from this platform. I am very pleased. The guiding was good. The stars were round, tight, and nicely formed, and crisp right to the edge of the field. Everything seemed to work as it should! So the next night of Astrophotography, I will have THREE rigs running!
More Information
Wikipedia: Messier 13
The Live Sky: Messier 13
Capture Information
Light Frames
20 x 30 seconds, bin 1x1 @ -15C, unity gain, ZWO Gen II L Filter
10 x 120 seconds, bin 1x1 @ -15C, unity gain, ZWO Gen II R Filter
10 x 120 seconds, bin 1x1 @ -15C, unity gain, ZWO Gen II G Filter
10 x 120 seconds, bin 1x1 @ -15C, unity gain, ZWO Gen II B Filter
Total of 1.3 hours
Cal Frames
45 Darks at 30 seconds, bin 1x1, -15C, Unity gain
45 Darks at 120 seconds, bin 1x1, -15C, Unity gain
30 Dark Flats at Flat exposure times, bin 1x1, -15C, unity gain
40 R Flats
40 G Flats
40 B Flats
40 L Flats
Capture Hardware
Scope: Askar FRA400 73MM F/5.5 Quintuplet Astrograph
Guide Scope: Sharpstar 66EDPHII
Camera: ZWO ASI1600mm-pro with ZWO Filter wheel with ZWO LRGB filter set,
and Astronomiks 6nm Narrowband filter set
Guide Camera: ZWO ASI290Mini
Focus Motor: Pegasus ZWO EAF 5V
Mount: Ioptron CEM 26
Polar Alignment: Ipolar camera
Software
Capture Software: PHD2 Guider, Sequence Generator Pro controller
Image Processing: Pixinsight, Photoshop - assisted by Coffee, extensive processing indecision and second-guessing, editor regret, and much swearing….. Given the problems on this image, more than the usual whining….
This is my third telescope platform - this one is specifically designed for portability and travel.