My telescope mount motor gave out during a deep sky session last night in Denver

I was 45 minutes into a 90 minute exposure of the Andromeda Galaxy when the RA drive just stopped tracking, ruining the whole stack. Has anyone else had a motor fail mid-session and found a decent replacement under $200?

2 comments

2 Comments

riley_coleman85d ago

45 minutes into a 90 minute exposure" on a mount that can't hold tracking for that long? That's on you for pushing gear past its limits. Most mounts under $500 are hobby grade and not meant for hour long subs. You're asking for trouble with a single 90 minute frame anyway. If your budget is $200, get a used Star Adventurer or an iOptron SkyGuider Pro and stick to 5 minute exposures with good polar alignment. That'll get you sharper stacks than trying to milk a cheap mount for long shots.

thea7045d ago

Yeah but not gonna lie, a 90 minute single sub on a Star Adventurer would be pushing it too lol. Even with perfect polar alignment, the periodic error on those budget star trackers is around 5-10 arcseconds over a worm cycle. After 45 minutes you're definitely gonna see some trailing unless you're using something like a 50mm lens. I've seen people get away with 10-15 minute subs on a Star Adventurer but 90 is basically asking for it regardless of budget.