M101_HaLRGB_25-3-2019

Well I F#£@ed 😡 this one up, as my teacher would have said “5/10 could do better, see me”.

60sec exposures were far to short for the luminance and I should have gone for 3min exposures on the RGB. To salvage something out of this I added the limited data (though longer exposures) I obtained of M101 two years ago, which were taken under less than ideal conditions.

As it has turned out better than my original version helped by adding the Ha and because I’m not going to revisit this anytime soon I thought I would post it anyway.

 

Object Description:-

M101 The Pinwheel Galaxy is a face-on spiral galaxy at a distanced of 21 million light-years away from Earth with a diameter of 170,000 light-years and has around a trillion stars, approximately twice the number that are in the Milky Way. M101 can be found in the constellation of Ursa Major. The Pinwheel Galaxy has a high population of H II regions where hydrogen gas is contracting under its own gravitational force resulting in stars formation taking place.

 

 

EQUIPMENT:-

Telescope Meade 6000 115mm and AZ-EQ6 GT

ZWO ASI1600mm-Cool cmos camera

Orion Mini Auto Guide

ZWO RGB Filter

Astronomik 12nm Ha Filter

Chip Temp Cooled to -20 degC

 

IMAGING DETAILS:-

M101 Pinwheel Galaxy (Ursa Major)

Gain 139 (Unit Gain)

New Data:

20 Red subs@120sec (40min)

20 Green subs@120sec (40min)

20 Blue subs@120sec (40min)

40 Lum subs@60sec (40min)

12 Ha subs@300sec (1h)

Old Data:

12 Red subs@180sec (36min)

7 Green subs@180sec (21min)

6 Blue subs@180sec (18min)

20 Lum subs@180 (1h)

Dithering

20 Darks

20 Flats

 

PROCESSING/GUIDING SOFTWARE:-

APT "Astro Photograph Tools"

DSS

PS CS2

Done