Peter_D

Reflectors that have a longer quoted focal length (e.g. 1000mm) than the actual length of their tube (e.g. 500mm) use a lens system before the focuser. These are Bird-Jones type reflectors and are not recommended for beginners: I don't have direct experience of one but from what I've read, they are very difficult to collimate. I have a 114/900 f7.9 reflector (tube is 800mm long) - because of its length, it needs a stable Equatorial mount but gives very good (comparatively narrow) lunar and planetary views - the longer focal length allows for higher mags to be achieved. Another advantage is that it holds its collimation well.

Thanks! IIRC, I zoomed around halfway - this was to get a sharp focus (using the Galilean moons helped).

My first attempt with video capture and stacking. Equipment: - Vixen r114m telescope - Huawei P9 smartphone - 25mm orthoscopic eyepiece - 5x Barlow lens Video capture converted to avi file and processed by Registax 6.

Thanks a lot for the prompt response, appreciate it!

Hi, My name is Peter and I am living in the locality of Cologne, Germany. I have a second hand Vixen r114m mounted on an unpowered GPE mount. I am relatively new to astronomy and a complete newbie when it comes to motors, axes drives etc My plan is to upgrade to a 150mm or perhaps a 200mm reflector later on in the year. Reading the above comments seem to indicate this is feasible. My question is what are my options for adding a RA-drive to the GPE? Are any non-Vixen modern ones I could use? Many thanks for any feedback! Peter