I’ve been trying out some different things over the last few weeks with my telescope and camera. Mostly I take photos by removing the eyepiece in the telescope and placing the camera there. This is called “Prime Focus” astrophotography. Even there I’ve been trying to push the boundaries a little bit.

Magnification is directly linked to the focal length of the telescope. This isn’t usually the main consideration in astronomy, where the size of the main lens or mirror is usually the principle characteristic. This is what controls its light gathering power and so determines the faintest objects it can see. My scope is relatively compact with quite a low magnification.

However, for planets and the moon, magnification is everything. You might have noticed that I’ve never posted any images of the planets and that’s the reason why. You need to add some extra optics to alter the focal length if you want to do planets with my scope. The result will never be as good as a dedicated instrument, but I can try. Here’s a single 1/200s iso 3200 shot of Jupiter.

That’s fairly typical of what you would actually see through the scope. I was hoping to get a few more over the last few nights, but weather, the moon, and me having to sleep sometime, have conspired to get in the way. To get improved results I need to take lots of images and stack them. This is most easily done by taking a movie. Here’s one of Saturn.

https://mega.nz/file/Ro4C3KTC#qwqi0L2sRXmHwE9wO8tH9om9PxEtq08ujE-g_jqB3DE

Unfortunately, my attempts to stack the frames from this haven’t worked out too well so far.

Increasing the focal length can also be used to get high magnification images of the moon.

This is the Mare Nectaris using this technique.

https://en.wikipedia.org/wiki/Mare_Nectaris

As well as increasing the focal length of the scope, I’ve also been experimenting with just using the camera directly. The problem I’ve always had with this in the past is that you need a really good tripod, with fine adjustments and preferably a motorised mount to track the sky. Expensive. Trying to take photos of the sky on an ordinary tripod has just proved too awkward.

However, I recently figured out a combination of lumps of metal, bolts and clamps that has allowed me to remove my telescope from its mount and put the camera directly in its place.

This has been great fun to use. It allows me to use the app on my phone to point the camera wherever I want and track it fairly accurately. It also lets me play with all the old lenses that are sitting in cupboards in the house. I’ve hardly begun to explore the possibilities here. At the moment I’m mainly using an old Pentax K mount f1.7 50mm lens. This has a field of view of about 15 degrees. perfect for Orion.

And Andromeda.

The way I’ve mounted the camera also allows me to balance it so that it isn’t front heavy. A big problem on a normal photographic tripod. This’ll let me play with some old telephoto lenses that are currently sitting unused. So I might be able to try out some new stuff in the months to come.