Leo Triplet (revisited)

The Leo triplet (also known as the M66 Group) is a well-known and beautiful group of galaxies located in the constellation Leo, at a distance of approximately 35 million light years. It is formed by the spiral galaxies M65 and M66 and by NGC 3628. 

When I added the Takahashi TOA-150 refractor to my equipment in 2009, this was the first object I targeted. The image I posted then and which is still on my website, with near 10 hours of exposure, is the first one on the right.

While I am accumulating exposure for new targets, I decided to reprocess this image in order to take advantage of: 

- The new tools incorporated in Pixinsight since 2009.

- The experience I have gained in combining images acquired at different resolutions and in processing the stream of my last image (NGC5907).

The second image is reprocessed from scratch. The original image was processed with PixInsight 1.4 (!), and now we are with version 1.8.9. Among the tools that I have used (and that were not present in 2009) I can highlight:

PhotometricColorCalibration

GeneralisedHyperbolicStrech

LocalHistogramEqualization

TGVDenoise

MultiscaleMedianTransform

Really a lot of them!

On the other hand, going through my archive, I found 4 hours of exposure taken the previous year (2008) with my other refractor (FSQ-106N): they are added and the image benefits from that. Therefore, the final image now accumulates 13.5 hours of exposure.

Click on the images for a full resolution version, or go to the Gallery section for a widefield version and complete exposure details