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NGC 7331, spiral galaxy in Pegasus. 46 mln light yrs away. Also in the picture are the galaxies NGC 7335, 7336 and 7337. They are estimated to be 300-400 mln light yrs away.


Image info

Telescope:  Skywatcher 8" f/5 Newtonian

Focus:  Prime focus

Camera:  SAC7B, uncooled

Exposure:  175 x 25s 

Date:  8th Sept 2002

Processing:  Acquired in Astrovideo as FITS.  Stacked in Iris.  Initially RGB, but converted to grayscale.


One of my first galaxy images.  At that time I was doing log stretching in Iris and struggled with getting a good transition between the sky background and the very faintest bits of the galaxy.  The sky background itself was not even and that had to be corrected using a synthetic background made in Iris.

I couldn't get any colour information out of this image at all, with the technique I was using at that time.

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