M 41

About image

M 41 is a bright open cluster in Canis Major constellation, also visible with naked eye a little south-west of Sirius.
It is located at a distance of 2300 light years: so considering its apparent dimension of 38’, we have that its phisical extension is about 25 light years.
Its estimated age is in the range 190/240 million years: it is a relatively young cluster, and indeed it contains several white/blue-white stars, but also some yellow stars.
I obtained this image from my backyard, which has a very bad sky in general (light pollution, humidity), but particularly for this object due to its low elevation on the horizon, so just in the directions of many street lamps.
The master frame RGB had horrible coloured gradients, but with some precautions in post processing (and also keeping the sky a little dark) I was able to obtain at least a decent image.

Technical data
Optic         Tecnosky Apo refractor LT 130-910 with Riccardi reducer 0.75x (focal lenght 692mm, f/5.3)
Mount       Skywatcher EQ8
Camera                      Moravian G3-16200 with external filter wheel 7 positions
Filters                         Baader 50mm unmounted RGB  
Guiding system         Artesky Ultraguide 70mm 
Exposure details    R 37x120" bin1 -20C

         G 47x120" bin1 -20C
            B 40x120" bin1 -20C
Total integration       4h8'
Acquisition                Voyager, PHD2
Processing                Pixinsight 1.8, Photoshop CS5, NoiseXTerminator, StarXTerminator, BlurXTerminator
SQM-L                       Bortle 8    
Location                    Rescaldina (Italy), home terrace
Date                          21/22 November 2023, 7 March 2024

© Roberto Marinoni 2019 - All rights reserved