Hi,

I usually update the time on the PC clock using Dimension4 each evening before I start observing. I've noticed (again?) that in the morning after a night of taking a couple hundred images, when I run Dimension4 to update the clock, the PC clock is always 30-50 seconds slow. In the evening, after a whole day of doing nothing, Dimension4 typically changes the clock by a second or less, and that could be one way or the other randomly!

I found this post from Dave Higgins that speaks to the same issue:
http://forums.dc3.com/showthread.php...lock#post15978

The issue for me is that, for eclipse minima timing, some precision is required, and a 30-50 second error probably doesn't cut it.

Was it decided that this is an SBIG driver problem - that downloading the image from the camera somehow interrupts the clock ticks in the PC? If I have a couple of hundred images and a 30-second clock error, that's about 150 milliseconds error per image. Seems like a lot to me, but the image typically takes a couple seconds to download. Or maybe the camera takes only 150 milliseconds to set up the download and the download is asynchronous.

Are there any new ideas about this, and have others who take lots of images per night noticed this?