Stacking 200 frames of the Horsehead, my tracking was off by 11 minutes

Last month I finally got a clear night in Ohio and tried to photograph the Horsehead Nebula. I set up my mount, did the polar alignment twice, everything looked good. But when I loaded the 200 frames into DSS the next morning, all the stars had little trails. I checked my logs and realized I had set the tracking rate to lunar instead of sidereal. An 11 minute mistake that wasted a whole evening of data. I found this out by reading an old forum thread about common mount errors, and sure enough, that was it. Has anyone else had a silly settings slip up that cost them a night? What do you double check before you start shooting?

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violatorres20d ago

Three years of imaging and I never once thought to check the tracking rate setting, figured it was one of those things that just worked out of the box. Then last winter I shot the Orion Nebula and got the same little trails you're describing, spent three nights trying to figure out if my polar alignment was off or the gears were worn. Turns out I'd bumped the hand controller while putting a lens cap on, switched it to lunar without even noticing. Your post just made me realize I should be cycling through every menu option before I start, even the ones I think I've got memorized... guess that's the difference between a quick setup and a wasted night.