On Tuesday night I placed my 8" telescope, roughly aligned, outside the observatory and attached the Canon 1000D to the photo bracket on top. I was using my old, russian 135mm f/2.8 lens stopped down to f/4. I got a consistent sequence of 83 photos of duration 15" at ISO 800 once the twilight had subsided from about 8:30BST (after having taken away the three where a plane grazed the comet). 15 seconds was the maximum I could get with the RA motor tracking before stars started trailing, because I'd had no time to align the mount. I stacked the pictures using Deep Sky Stacker and after about 10 attempts at processing, removed the gradient. Then I blurred the background and enhanced the faint features by brightening them, hence you can see the whole fan shape of the comet. The total exposure time was just over 20 minutes (with much more time taken up recording calibration frames). Just think... the Andromeda galaxy must look amazing from the comet! :)
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