M31 - Andromeda galaxy
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This spiral galaxy probably looks similar to our own Milky Way if it were possible to see that from 2.5 million light years away. Bands of interstellar dust are quite clearly visible. Two small companion galaxies (of dwarf elliptical type) can also be seen in this photo: M32 is the more compact one on the upper left (it looks like a bright star); M110 is the more obviously galaxy-like one on the lower right.
M refers to the 18th century catalogue of Charles Messier.
Camera only, from dark site
Canon EOS5DMkII 100-400mm lens @ 400mm 32 x 30s f/5.6 ISO3200 2010-12-11 18:09:33-18:27:38 UT
From Rookhope 54.8
The camera was on an HEQ5 mount, driven but not guided.
Camera only, from light-polluted site
Canon EOS 5D MkII, ISO 3200
100-400mm lens at 400mm f/5.6 HEQ5 mount
180 x 16s on 2013 October 29 at 20:20:12-21:45:26 UT
From Whitley Bay 55.1
This is from a light-polluted site. The 2 small satellite galaxies M32 and M110 have come out well.
Through telescope, from dark site
The core of the galaxy. It is too large to fit completely into the field of view of the telescope. The telescope was on an HEQ5 mount, driven but not guided.
Canon EOS5DMkII 254mm Newtonian @ 1200mm 65 x 30s f/4.8 ISO6400 2010-12-11 19:58:54-20:37:10 UT
From Rookhope 54.8
Through telescope from light-polluted site
Canon EOS5DMkII 254mm Newtonian @ 1200mm 52 x 10s f/4.8 ISO6400 2009-9-26 21:49:17-22:05:39 UT
From Whitley Bay 55.1
Minimal equipment - fixed tripod
There was an unusually clear sky in light-polluted Whitley Bay. I tried some experiments on a fixed tripod for the purpose of demonstrating what is possible with minimal equipment. Exposures must be short to avoid trails but if enough exposures are taken at high sensitivity (ISO 6400) it is possible to use software to cut through some of the light pollution.
Perseus, Cassiopeia, Andromeda & Pegasus
First a reminder that single frames look awful. Do not be put off by that. Take lots of them and use software, as I will show.
Canon EOS 5D MkII ISO6400 8s 24-105mm lens at 24mm f/4.5
Fixed tripod 2012 Sep 11 22:40:50 UT
From Whitley Bay 55.1
148 of those were stacked in GRIP, followed by some background correction and tone curves to make this:
Canon EOS 5D MkII ISO6400 148x8s 24-105mm lens at 24mm f/4.5
Fixed tripod 2012 Sep 11 22:40:50-23:12:54 UT
From Whitley Bay 55.1
The image above has been scaled down from an initial 3609 pixels wide to 600 pixels. Taking a crop at full size around M31 looks like this:
Not bad for a fixed tripod in light-polluted suburbia?
How to find M31
I use an annotated version of the previous picture in my talks, to show how to find M31:
The camera detects far more stars than can be seen with the naked eye and this makes it more difficult to pick out the shapes of constellations in these images. In the photo above, the camera has picked up rather well the double star cluster that lies between the W shape of Cassiopeia and the elongated constellation of Perseus below it. In the photo the double cluster appears as 2 bright dots. They are just about visible to the naked eye from a dark site. A pair of binoculars or a telephoto lens reveals hundreds of stars in each of those dots.