Star Clusters

M13 first light with Esprit 100 triplet refractor

So I finally had some clear skies to collect some data using the new Esprit 100 triplet refractor. This data was taken without the use of the field flattener that comes with the telescope. I have to get a custom spacer/adapter manufactured in order to attached my camera/filter wheel to the field flattener. That is in the works. This data was taken early July 2017 and is a SynthL-RGB image meaning no luminance data was collected. Instead a synthetic luminance channel was created using the R-G-B channels.

M13 globular cluster imaged with an Esprit 100 triplet and ASI1600mm-c

This is globular cluster M13 in the constellation of Hercules. It is visible in binoculars and small telescopes. There is about 300,000 stars within it. M13 was discovered by Edmond Halley in 1714, and cataloged by Charles Messier on June 1, 1764. In 1974 a message was beamed to M13 from the Arecibo Observatory as an experiment in contacting potential extraterrestrial civilizations in the cluster.

Imaged with a Sky-Watcher Esprit 100 F5.5 Triplet telescope
ASI1600MM-C ZWO Astronomy Cameras
XAGYL FW with 2″ Optolong RGB filters
Total of 1-hour and 12min of data
Processed in Pixinsight.
Data was collected by me and processed by my friend and fellow astrophotographer Ron Brecher (

Shawn Nielsen

My story began nearly 40 years ago looking up at the Moon with a small collapsible telescope my Father had. Encouraged by my parents, who bought me my very own telescope, a 4.5" reflector, I began to explore the night sky from my family home backyard. Today I do astrophotography from my home in Kitchener, Ontario and also with remote telescopes located in New Mexico and Australia. Some of my images have won awards and have been featured online and in magazines.

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