Spiral Galaxy ... Messier 100
(Click on Picture for larger view)

Added May 4, 2018 ...
Messier 100 is a spiral galaxy located in the southern part of the constellation of Coma Berenices ... (Nearly high overhead at 11 pm in early May). This is the furthest object that I have ever photographed ... 55 to 60 million light-years away!!! This galaxy contains about 400 billion stars, as compared to about 250 billion in our own Milky Way Galaxy. According to its 'red shift' it is moving away from us at around 1,525 km/sec ... much faster than the Pinwheel Galaxy which is moving away at 360 km/sec! This image was rather difficult to process but I was able to stack 21 of the sub-frames which were 150 seconds each giving a total exposure time of 52min 30sec. I've just about pushed to the limit of seeing distant galaxies with any type of fullness with my telescope within my backyard in a 'yellow' light-polluted region.

The Techy Stuff: ... For those who want to know ...
Telescope: Celestron Edge HD 11" with a 0.7X field reducer
Focal Ratio: f/7 (with Reducer)
Camera: Altair Hyperspace 183C CMOS at gain 35
Capture software: Altair Capture
Guiding: 50mm guide scope with Orion StarShoot AutoGuider
Guiding Software: PHD2 ...
(RMS Error 0.69 of 1 second of arc)
Filter: CLS (City Light Suppression)
Exposure: 21 sub-frames at 150 seconds each
Dark Frames: 10 sub-frames at 150 seconds
Stacking: Photoshop CC ... Manually
Post Processing: PixInsight & Photoshop CC
Mount: Celestron CGEM II GoTo EQ Mount
Outside Temperature: 67°

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