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QHY174M-GPS - Stop time with Cal LED

Posted: Sun Feb 11, 2018 10:29 pm
by SteveInNZ
SharpCap Pro 3.1.5022

If you turn on the Calibration LED, the time from the camera freezes. The difference between the GPS and PC clock increases accordingly.
Turning off the Calibration LED doesn't fix the time freeze but moving either of the Calibration Start/End sliders does.
Checking back, this occurs with versions 2.9 and 3.0 too.

Steve.

Re: QHY174M-GPS - Stop time with Cal LED

Posted: Mon Feb 12, 2018 7:02 am
by admin
Hi Steve,

The theory with the calibration LED is that you turn it on, adjust the start and end values based on whether you see the LED glow onscreen and then turn it offf - at that point your timing should be microsecond accurate to GPS time.I think the calibration procedure is to adjust the start to the lowest value where you get to see the LED light glow and the end to the highest value where you see it, but I haven't done it for a while. You need to recalibrate if you change exposure and possibly other camera parameters as they affect the exposure timing...

Unless you truly need microsecond accuracy on the frame timings I'd advise leacing the calibration alone. You should be good for timings to at least the millisecond level without touching it.

cheers,

Robin

Re: QHY174M-GPS - Stop time with Cal LED

Posted: Mon Feb 12, 2018 7:03 am
by admin
I didn't really make my point in the above post... I guess the point is that the only reason to turn the LED on is to adjust the start/end values, so the workaround for the bug is built into the usual operating procedure.

cheers,

Robin