MotoFocus
I’ve had motors attached to the focusers of my photographic scopes for about a year now and it’s been a tremendous learning experience as well as a boon to well, being focused!
There were a whole bunch of things that made themselves apparent that I hadn’t known to consider until they happened to me, so I thought I would share my experience with the astrophotography community so people would have a good ‘heads up’ if they were considering going this route.
As we are entering what feels like “Phase Two” of the Covid19 virus in 2020 I find myself with more time on my hands than ever since were are still not really open as usual around here. All my stargazes are cancelled until next year at the earliest, and we have had maybe two or three clear nights at most in the last three months so there’s been very little astrophoto activity possible.
I’ve been doing a lot of research and development along a few new areas so when/if we get some clear skies as we head into Autumn/Winter I’ll have some new game ready to go.
First, I’ve made the jump to monochrome imaging in conjunction with a filter wheel for it’s enhanced resolution. I didn’t really want to but my color camera has become so unreliable that it’s just unusable and I’m finding it’s really tough to get service on these things, even when you buy from a major dealer. Monochrome is the next step forward anyway so if you’re going to spend money you might as well keep making progress. When I get the color camera fixed I’ll be able to put up two complete imaging rigs and image the same object in both color and monochrome which should lead to some spectacular pics I’m hoping.
Monochrome presents some challenges: you get color images from a black and white camera by shooting the same object through a series of colored filters and then combine them all as a color image in the computer while processing. The filters are arranged in a wheel that’s controlled by the shooting computer so it can automatically switch the filters when required which is terrific but there’s no guarantee that focus is going to be exactly the same from filter to filter so you need to test and experiment to discover if you’ve got an issue in these areas. I’ve got six filters installed in my seven position filter wheel and one of the filters needs to be 70 focus steps further in than all the others. It took two hours of repeated autofocus runs to find that out.
The new QHY600 camera is really wide field and extremely detailed. I’m expecting to make some progress with it but ya gotta have an entire clear night to take enough data with 4 filters to get a good shot.
Here’s hoping,
Bill Gwynne
aka Bill the Sky Guy