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The key to using any mount successfully is taking the time to align it perfectly. In the northern hemisphere you have to align the mount with the pole star, and also the latitude of your location.

Next you need to aim the telescope at your subject. Some mounts, often referred to as GoTo mounts, have a computerised database where you simply choose an object and the mount will automatically move the telescope to its position. Alternatively, you can use an online star map or an app to find the object, and manually position the telescope.

Now you’re ready to shoot. Take several images using an exposure of one to five minutes, along with dark and light frames to help eliminate optical defects and noise. A dark frame is shot using the same settings as your main exposure, but while covering the telescope.

Finally, you can combine all of your images using Photoshop or dedicated stacking software. One of the most popular specialist programs is DeepSkyStacker. Available for Windows, it’s free to download from http://deepskystacker.free.fr. DeepSkyStacker gives you a choice of stacking methods to help you achieve accurate results, and accepts all major raw file formats as well as JPEG. Basic post-processing tools are included.

YOU’RE A STAR! Steve Loughran www.steves-astro.com Amateur astronomer Steve set up his equipment in his Cambridgeshire garden to get incredible images of stars and constellations. “A really good image can take as long to process as it does to...