MaxIm users - do you use Astrometric Resync?

[troypiggo]

I'm working on reducing my flexure, but on top of that I noticed this feature in MaxIm where after a set number of exposures, you can set it to plate solve an image, sync and slew back to the coords it should be at. Thought this could be handy because the flexure was so bad after 10-20 images, things did start creeping across the frame.

Does anyone use this? Every time? Do you use the "Sync Telescope" one, or just the "Correct via Slew" one where it doesn't actually sync?

[DavidTrap]

I haven't used the automatic feature, but my usual procedure is:

frame the object as desired
take a run of images (30-90mins)
change filters
slew to a 4th mag star - run focusmax
open first image & platesolve
recentre to those co-ordinates
take another run

I could add in a platesolve and resync on the 4th mag star to ensure the scope knows where it is pointing, before I swing back to the image co-ordinates.

Does that make sense? I suppose as I am refocusing between each filter, or every 60-90mins when shooting luminance or Ha, I haven't felt the need to automatically resync. I'm also using an OAG, so shouldn't have a flexure issue either.

DT

[Octane]

I use the solve only feature after every exposure. This allows me to use the astrometric stacking algorithm for precise stacking.

H

[troypiggo]

Gotchya. Makes sense, thanks David. Not going to Astrofest? I'm there this Thurs. If this flu hasn't killed me in the meantime... see below :D



G'day H. Sorry, been a bit quiet last week or 2. Got this flu that just won't go away, got doc appt tomorrow, could be swine flu! No jokes about my surname please :)

Haven't seen or attempted that astrometric stacking. Will look into it. So the solve adds coords to the FITS headers I assume? Neat.

[Octane]

Precisely. :)

Get better soon!

H

[Moon]

Sometimes I plate solve before I start or after a meridian flip to get the scope pointing in the right place.
During an imaging run I just dither between exposures. I believe (from memory) you can't dither and astrometric resync. It has to be one or the other unless you use ACP or something like that.

I guess your flex is giving you all the dithering you need, but I think it would be better overall if you could somehow stop that drift and start to dither. Perhaps an OAG or rearrange the guide scope setup?

James

[troypiggo]

Thanks mate. Yes, I've been doing a plate solve first up for alignment. Very cool, and accurate. And as you mention, dithering didn't seem necessary because of the excessive flexure. I've made some changes to the guide scope support now and hoping to have reduced it a bit, but won't know til field test.