So, I just took 9 fifteen minute subs of the Angelfish in H-alpha. But they show small amounts of trailing. The five minute test was completely fine. I stopped guiding and tightened everything down -- especially the Dec and RA lockdown finger screws.
The trailing appears up and down generally in a N-S direction which I think corresponds to Declination.
I'm waiting for a test exposure. If it shows the same trailing, I may try guiding only in one direction for DEC.
It could be the camera mount. I just don't know of a better way to secure that stupid camera mount. There's so much opportunity for slippage with that single 1/4-20 bolt/screw.
[Little later...] Still trailing, but appears slightly (25%?) less. I just swtiched to Dec corrections only in the South. If that helps even more then maybe that points to DEC backlash?
Also, this could be all differential flex. I'm using a dual-saddle configuration, guiding with a 80mm refractor on one side and the camera on the other.
What's weird is that I'm not having these problems with the Tak102 and a guidescope which weighs like twice as much. That makes me think there's flex in this system somewhere.
[Little later...] It's 9 degrees outside. My ass is cold. Literally.
The last sub had some trailing -- better than before, but still.... ARGH!!!!
I initiated the Meridian flip, re-focused (not sure I did a good job as my fingers were frozen),
re-calibrated PHD and started another run of 15 min subs.
[End of the session...] Guiding went to crap at around 3 arc sec RMS. Still showing that weird vertical guiding error.
Things to try:
1) Disassemble the dual-saddle and tighten everything down.
2) Do another polar alignment.
3) MOVE both the camera and guidescope to one side.
4) ADD more weight on top by adding maybe another camera.
5) Cover the connection of the USB-Serial module w/hand warmers. Maybe the
electronics are getting too cold???
So frustrating..... :(
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