Hot on the heels of my recent post about telescopes for imaging, in this post I’d like to share with you the very first image taken with my new GSO 6″ f/5 imaging Newtonian – which was funded by selling my two previous telescopes and a couple of camera lenses.
Tonight was the first clear night since buying the telescope so I headed to my dark site in Somerset. It was a bit hazy but good enough to test out the new telescope. The Advanced VX mount is rock steady and makes my previous entry-level mounts feel like mere toys. The telescope itself feels like a proper scientific instrument.
The first object I slewed to was Messier 31, better known as the Andromeda galaxy.
This image is a stack of 35 frames, each exposed for 30 seconds – which is the longest my camera can do automatically without an intervalometer. I do have an intervalometer but for testing, 30 seconds exposure is sufficient and is already an order of magnitude longer than my previous tripod could do without being affecting by motion blur. In future I will try unguided exposures of a minute or longer which should reveal even more detail. I also included one dark frame to help with the noise.
I’m still finding my way with astronomy image processing. These pictures were aligned and stacked with DeepSkyStacker and then I used the just green channel as a monochrome image in an attempt to avoid light pollution.
It also looks like the telescope needs collimation as stars which should render as points of light are appearing as small triangles. However, image quality otherwise blows me away compared to any telescope I’ve used before. The coma corrector in particular plays a useful role in ensuring sharp images all the way to the corners.
I was ready for more photography, but it started to get a bit misty so I called it a night. In summary, I am extremely pleased with this image as a very first attempt using this telescope and mount. With practice I hope to improve my skills with the telescope and my skills with processing software. Watch this space for my future attempts 🙂
Jonathan Gazeley 