The Galaxy
The Sombrero Galaxy (M104) is 30 million light-years away in a low density area of Virgo. The Sombrero though is a massive galaxy, over 10 x more massive than our own Milky Way Galaxy. Astronomers have puzzled over the morphology, a combination of a massive  bulge/inner halo, a more extended spherical external halo, and a dusty disc nearly edge-on. The details of the structure suggest it is an elliptical galaxy, not an edge-on spiral.

Tidal Tail (see Martinez-Delgado for more details, and my animation for the location)
It is proposed that the odd composition of globular clusters in M104 was produced by a recent merger, with metal-poor blue clusters from an old elliptical galaxy, and metal-rich red globular clusters and halo stars originating from a companion galaxy. To this end, such a merger may have left a tidal tail, which indeed was discovered in 1997 from UK Schmidt Telescope (UKST) silver halide plates taken in blue light, by a special method emphasizing the faint details in the surface of the plate. The result has been confirmed in more recent images. The huge visible tidal stream was used to create a computer model of the trajectory of particles in the tail. There is a short video here, or refer to the paper. It is believed however, that this tail is from a minor galaxy merger that took place between 3.5 and 3.0 Giga years ago, and that the major merger that created the current M104 morphology took place earlier than this.

My Processing
I produced individual LRGB stacks using DeepSkyStacker with 2X drizzle, as the data appeared a little under-sampled. I composed the image in StarTools, cropping and binning slightly (bin =0.71), followed by wipe (background extraction), autodev (with some adjustments to gamma and linearity), HDR, deconvolution, color, star reduction and a superstructure isolation. In Photoshop I did an APF-R multi-scale unsharp mask (on the galaxy disk only), Astronomy Tools Deep Space Noise Reduction, and overall noise reduction with NoiseXterminator.

The gif animation shows my processed image inverted, the inverted image from 1997, and a rough positioning of the tidal stream model as a guide to where the tidal stream is located. 

Raw Data from Insight Observatory ATEO-1: 
Dreamscope 16" f/3.7 Astrograph
Software Bisque Paramount ME
FLI Proline 16803 Camera
RGB each 20 x 5 m = 100 m 2021-05-01 to 05-13; 
Lum 55 x 5 m = 275m 2021-05-01 to 05-11
Beryl, Utah USA (Utah Desert Remote Observatories)