Messier 96 in Leo

Messier 96 is an intermediate – showing both barred and non-barred characteristics – spiral galaxy located about 31 million light years away. The galaxy is a member of the Virgo Cluster. It is categorized as a double-barred spiral galaxy, with a small inner bulge through the core along with an outer bulge. The core appears to have a supermassive black hole with a mass between 1.5 and 48 million solar masses. It’s a member of a small group of about a dozen galaxies known as Leo I, several of which are bright Messier galaxies.

Seen through the lower spiral arm is the flat galaxy 2MASX J10465229+1150201. This is one member of a galaxy cluster centered about 725 million light years away. The dominant galaxy in this cluster is PGC 83335, the bright elliptical located just outside the galaxy halo at upper right. Most of the brighter background galaxies in this image appear to be members of this cluster. I haven't been able to find a catalog designation for it.

Exposure: Total exposure time about 10.5 hours, 211:36:34:36 x 2 minutes LRGB. All bin 1x1. Data collected in April and May 2019.
Light pollution: Bortle 7-8 (white zone, NELM about 4.5)
Seeing: Average FWHM of subs around 2.45 arcsecs
Image scale at capture: 0.6 arcsecs/pixel = f/5.7
Scale of presentation: 1.2 arsecs/pixel (50% of full scale)

Equipment:
Scope: C11 (standard, not Edge) with Celestron 0.63 reducer
Mount: Paramount MX+, connected via ASCOM Telescope Driver 6.1 for TheSkyX, with MKS 5000 driver 6.0.0.0
Camera: SXVR-H694, connected via SX ASCOM driver 6.2.1.17140 (SX 1.2.2 also installed)
Filter wheel: Atik EFW2 with 7x1.25 carousel and Artemis 2.4.3.0 driver
Filters: Astrodon 5nm Ha/SII, 3nm OIII, Type IIi LRGB
Rotator: Optec Pyxis 2", connected via Andy Galasso's 0.4 driver (Optec Pyxis Rotator AG)
Focuser: Rigel Systems GCUSB nStep motor with driver version 6.0.7 on stock Celestron focuser
OAG: Orion Thin OAG
Guide cam: Lodestar (first generation). 4 second exposures
Automation SW: Sequence Generator Pro 3.0.0.8
Guide SW: PHD2.6.3, connected to guide cam via native SXV driver
ASCOM: ASCOM 6.3.0.2831
Platesolving: PlateSolve 2, failover to local Astrometry.net 0.19 server
Collimation: Metaguide 3, using ASI120MM connected via ZWO Direct Show driver 3.0.0.2
Processing Workflow by Workspace in PixInsight 1.86

1. Calibration
BatchPreProcessing with flats, darks and bias, using Cosmetic Correction with master dark
Blink to preview and reject a few frames
Subframe Selector for luminance to confirm selections and weight by FWHM and SNR
StarAlign to register frames

2. Stack and Mure Denoise
Image Integration on each channel
Mure Denoise basically had no effect, so I didn’t use it
RGB Combination for RGB frames
Dynamic Crop

3. Luminance Linear Processing
Dynamic Background Extraction
Deconvolution with Dynamic PSF and star mask for deringing support. Masked in using mask created in Photoshop.

4. Luminance Stretching
Histo Trans x 3
Curves Trans
TGV Denoise
Aggressive Multiscale Median Transform to remove lumpiness in background, using an inverted and blurred luminance frame as a mask to protect highlights

5. RGB Linear Processing
Dynamic Background Extraction
Photometric Color Calibration

6. RGB Stretching
Histo Trans x 3
Boost saturation in galaxy with Curves Trans and luminance mask

7. Color Combination
LRGB Combination of luminance and RGB images

8. Star Repairs and Background Removal
Photoshop: Create an artificial flat by eliminating the remaining small stars with the Dust and Scratches filter
Subtract the artificial flat from the main image, masking out the galaxy
Use Radial Blur filter to obscure comatic blue halos on bright stars

9. Final
Final Histogram Transformation
Final saturation boost with Curves Trans
Resample to 50% of scale
Save both images as JPGs