I am interested in getting one of the iOptron SkyGuider mounts to get into some basic Astro Photography. I know next to nothing and thought that one of these "tracker" units would maintain precise tracking indefinately once set up.
From what I have read that does not appear to be the case due to positional error (PE). Can someone explain what PE is and is this something that cannot be overcome? Would a SkyGuider track accurately long enough to allow good photos?
I'm guessing the answer is yes, as from what I have read most exposures seem to be no longer than about 3 minutes? Would appreciate any insight into the possible shortcomings of trackers.
PS:So can this tracker take 4 to 5 min subs say with a 200mm lens? If you can only get 60 sec subs might as well make a barndoor tracker and save yourself the money.
What is meant by "subs"??