Motorized Focusers

In my last post, I told you I was dusting off the RC telescope to get ready for galaxy season. I managed a few galaxy shots, but had finally had my fill of the scopes stock focuser. The focuser is by far the weak point of the GSO RC's. I also like to rotate through the RGB filters when getting my color data. This is difficult to do when the focus points of each filter are not the same. I decided to go with the Moonlite CSL 2.5" Large Format focuser with High Resolution Stepper Motor. What a fine piece of equipment this thing is! It is really a work of art.

I chose the M68 threaded drawtube version. It came with 2" and 1.25" threaded ends with compression ring and thumbscrews. I may eventually purchase the M68 to M48 adapter to make the entire image train threaded. It seems to be working just fine like it is though.

The grey piece hanging off the motor is an adapter I got from Rigel Systems for $10. This adapter lets me use my Rigel controller that I purchased a while back along with a stepper motor for my TS 107mm triplet.

This is my second Moonlite focuser that I have bought and I really like them a lot. The Teleskop Service 107mm scope came with a nice 3" rack and pinion focuser so I decided to keep the focuser and just order the Rigel Systems kit for it. Here are a few shots of the Rigel setup on the TS107.

Rigel usb-nStep controller

Both of these work great with Sequence Generator Pro. Once focused you can save the focus position and it will automatically go to this preset position when the filter is changed. It also allows for autofocus, which can be programmed by temperature if you wish. You can also set it to run autofocus upon a filter change, once an hour, or a number of other options. Once autofocus is ran there is a box that can be checked to adjust the focus points of the other filters by the same amount.

The guys at The Astro Imaging Channel have a really good video that goes into this much more than I can here. If anyone is interested it can be found here.

Galaxy season was just getting started when I last posted in March. I have several more since then, all taken with the RC, along with the Globular Cluster M13, and the interesting planetary nebula Jones-Emberson 1. These can all be seen in my Astrobin gallery.

The motorized focusers are really very nice and I'd hate to be without them now. I was reminded of this last night when I got out my William Optics Star71. This scope has a nice 2.5" rack and pinion focuser and it will be receiving a Rigel motor very soon!!! I was able to get in a couple hours of luminance data with it before the clouds moved in. I am very excited about this image and am hoping to get some good skies to finish it soon. This is just 6 subs of 1200 seconds each on NGC 7023, the Iris Nebula, and the surrounding dust in the region. I'll leave you this month with this work in progress. I hope to share the finished image soon! :)