Neat shots Brian. I have a number of telescopes I did peer through but recent street lighting changes have wrecked that and as you mentioned photo's though a telescope make things more than a touch more complicated. If I do that now I need something really portable that also works. This might interest you. It's been an ongoing project for a long time now.
https://www.cloudynights.com/topic/5...rophotography/
There are others based around indi - that can also be PC based but it seems to be more complicated to me. You might also like to spend some time googling barn door trackers. Design's vary. The main thing they need is a rigid hinge.
Thanks for reminding me of the 500 rule. I did try this once only to find that the camera I had with me went into a strange mode and stacked itself rather than actually using the exposure I had set.. I wasn't sure what camera settings to use so when I have a go again I'll try yours just accounting for the lens focal length.
One query though. I thought that the stacking software also aligned so tracking can be extremely rough ??
John
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