Messier 51 - Whirlpool galaxy

Re-processed 12th October 2021

 

M51a (Whirlpool Galaxy) interacting with its companion galaxy NGC5195 23 million light-years away. The star bridge/dust cloud connecting the galaxies are a result of the gravitational interaction which has estimated to have been ongoing for the last 500 million years. This interaction will eventually cause the two galaxies to merge.

 

Equipment:

 

Skywatcher HEQ5-pro (Rowan Belt Mod)

 

ZWO ASI 294MC-pro

 

Explore Scientific ED APO 102mm F7 FCD-100 Triplet Carbon Fibre

 

Hotech SCA 1x field flattener

 

ZWO ASI-120MM-mini guide camera

 

Skywatcher Evoguide 50ED guidescope

 

2 inch mounted Optolong L-Pro

 

Acquisition:

 

Sharpcap polar alignment, ASCOM guiding/dithering with PHD2

 

APT image acquisition

 

Lights – 100 x 180s at -15c, gain 125, offset 30 (total integration 5 hours)

 

Darks – 30

 

Flats – 30

 

Dark flats - 30

 

Procesing:

 

Images calibrated and stacked in APP

 

Light pollution removal and star colour calibration in APP

 

Autostretched image saved as 16 bit TIFF

 

PS – star saturation, masked stretch to reveal faint outer dust, high pass filter on galaxy (pixel size 5) with layer mask, further saturation enhancements, denoise of background, black point set to 25, starnet++ used to reduce star size/burden.

 

Minimal crop

Done