Globular Cluster M10

 Globular Cluster Messier 10

M10 was discovered by Charles Messier on May 29, 1764. It was not until German-born British astronomer William Herschel observed the cluster with a larger telescope that M10 was resolved into individual stars and recognized as a cluster. 

Constellation: Ophiuchus

Distance: ~ 14,300 lys

Magnitude: 6.4

Age: ~11.39 billion years

Stars: ~100,000

https://www.messier-objects.com/messier-10/

CAPTURE INFO

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Scope Centering:

- RA:  16h 57m 8.92s

- Dec: −04° 05′ 58.07″

Bandwidths:

R, G, B, L

Date Captured:

June 14, 2021, Club Dark site (Bortle 4)

GUIDING NOTES:

Average, averaging ~1.0 RMS

IMAGE CALIBRATION (PixInsight)

Weighted Batch Preprocessing

- Lights, Darks, Flat Darks, Bias

- Cosmetic Correction

- Stats

  - R (20) 60 second subs

  - G (20) 60 second subs

  - B (20) 60 second subs

  - L (30) 30 second subs

NON LINEAR PROCESSING (PixInsight)

1. Dynamic Crop

2. Automatic Background Extraction

3. Dynamic Background Extraction

4. Linear Noise Reduction to each channel using MultiscaleLinearTransform

5. Another Linear Noise Reduction using MultiscaleLinearTransform

6. Linear Fit was applied to R, G & B using L as base.

7. Channels were combined with ChannelCombination

LINEAR PROCESSING (PixInsight)

1. Histogram Stretch

2. Starnet++ to remove the stars and create a image of the stars

3. Used the Game script to create a gradiant mask for the Globular Cluster; applied mask and inverted.

5. (Starless Image) Used Histogram to reduce the background skyglow/light pollution.

6. (Starless Image) TGV Denoise to remove more noise

7. Removed Red Star bloat from background using Clone Stamp

7. (Stars Image) Increased saturation of the stars using ColorSaturation

8. Added stars to the background using PixelMath

9. Inverted image; ran SCNR red and blue reduction by 50% to reduced halos around stars.

10. Made image ready for the web using ICCProfileTransformation

EQUIPMENT

Optics: SGO 6" f/4 Imaging Newtonian @ 610mm FL

        Baader 2" Coma Corrector

Camera: ZWO 294mm Pro (mono)

Filter Wheel: ZWO 8 position, .36" filters

Filters: 

 - R (Baader Planetarium LRGB 36 mm Round CCD Filter )

 - G (Baader Planetarium LRGB 36 mm Round CCD Filter )

 - B (Baader Planetarium LRGB 36 mm Round CCD Filter )

 - L (Baader Planetarium LRGB 36 mm Round CCD Filter )

Mount: 

- Losmandy GM811

- RAEXT EXTENSION DOVETAIL

- Losmandy 12" Tripod Extension

- Losmandy SADDLE PLATE FOR G-11 MOUNT

- Losmandy 16" UNIVERSAL DOVETAIL PLATE

- Losmandy LW Tripod

- Alt-AZ/Elevation Tensioning bolts and washers (Michael Herman's)

Guiding: 

- ZWO 120mm mini (red filter)

- Agena 60mm f/4 Guide Scope with Helical Focuser

- PHD2 Software (2.6.9 Dev 5)

  - Multistar option

  - RA algorithm:  Predictive PEC

  - Dec algorithm: Resist Switch

- Used previous calibration done

- Dither: Small, every 3 frames

  

Acquisition: 

- ASI Air Plan Mode

- Flats & FlatDarks using NINA Flat Wizard