The Great Hercules Cluster | M13
The Hercules Cluster is a large collection of stars called a globular cluster. Globular clusters are gravitationally bound densely packed groups of stars; it is estimated the Hercules Cluster contains ~300,000 stars. As the name suggests, it is found in the constellation Hercules and is easily visible with binoculars or a telescope. This cluster is ~25,000 lightyears away from Earth and ~145 lightyears across.
I love observing the Hercules Cluster through my telescope as it is one of the brightest globular clusters visible in the northern hemisphere. When I invite the public to view the night sky through my scope it is one of the objects we often look at.
Shot from my backyard near Taos, New Mexico.
Equipment:
SkyWatcher EQ6-R Mount
Nikon 800mm f/5.6 AI-S - shot at f/8
Nikon 1.4x Teleconverter
Sony a7RIII (unmodified)
ZWO 30mm Guide Scope
GPCAM2 Mono Camera
Acquisition:
Taos, NM: my backyard - Bortle 3
55 x 121" for 1 hour 50 min and 55 sec of exposure time.
8 dark frames
15 flats frames
15 bias frames
Software:
SharpCap
PHD2
PixInsight
Lightroom
Photoshop
My a7rIII and adapted Nikon 800mm f/5.6 AI-S lens were mounted to my SkyWatcher EQ6-R mount using a vixen rail. The guidescope/camera were fixed to the front of the rail. I used SharpCap to achieve "excellent" polar alignment. I shot ISO 1600, f/8 with a 1.4x teleconverter, making the focal length 1120mm. I took 121" exposures using PHD2 with my guidescope to keep tracking accurately. I brought the lights/darks/flats/bias frames into PixInsight for stacking and aligning and then used: STF, Cropping, Dynamic Background Extraction, BlurXTerminator, plate solving, color correction, NoiseXTerminator HDR, and then the background of the cluster was separated from the stars using StarXterminator, and both files processed and stretched separately and then recombined using PixelMath. That file was brought into Lightroom for Metadata and EXIF tags, light post-processing, and cropping. I used Photoshop to sharpen the final image.
The Great Hercules Cluster | M13
The Hercules Cluster is a large collection of stars called a globular cluster. Globular clusters are gravitationally bound densely packed groups of stars; it is estimated the Hercules Cluster contains ~300,000 stars. As the name suggests, it is found in the constellation Hercules and is easily visible with binoculars or a telescope. This cluster is ~25,000 lightyears away from Earth and ~145 lightyears across.
I love observing the Hercules Cluster through my telescope as it is one of the brightest globular clusters visible in the northern hemisphere. When I invite the public to view the night sky through my scope it is one of the objects we often look at.
Shot from my backyard near Taos, New Mexico.
Equipment:
SkyWatcher EQ6-R Mount
Nikon 800mm f/5.6 AI-S - shot at f/8
Nikon 1.4x Teleconverter
Sony a7RIII (unmodified)
ZWO 30mm Guide Scope
GPCAM2 Mono Camera
Acquisition:
Taos, NM: my backyard - Bortle 3
55 x 121" for 1 hour 50 min and 55 sec of exposure time.
8 dark frames
15 flats frames
15 bias frames
Software:
SharpCap
PHD2
PixInsight
Lightroom
Photoshop
My a7rIII and adapted Nikon 800mm f/5.6 AI-S lens were mounted to my SkyWatcher EQ6-R mount using a vixen rail. The guidescope/camera were fixed to the front of the rail. I used SharpCap to achieve "excellent" polar alignment. I shot ISO 1600, f/8 with a 1.4x teleconverter, making the focal length 1120mm. I took 121" exposures using PHD2 with my guidescope to keep tracking accurately. I brought the lights/darks/flats/bias frames into PixInsight for stacking and aligning and then used: STF, Cropping, Dynamic Background Extraction, BlurXTerminator, plate solving, color correction, NoiseXTerminator HDR, and then the background of the cluster was separated from the stars using StarXterminator, and both files processed and stretched separately and then recombined using PixelMath. That file was brought into Lightroom for Metadata and EXIF tags, light post-processing, and cropping. I used Photoshop to sharpen the final image.