Trouble connecting RCOS rotator to MaxIm Observatory window

[Dan Simpson]

Hi All,
I'm cross-posting this note I sent to the Diffraction forum to see if anyone here has any suggestions.

What I'm trying to do is get MaxIm's Observatory window to connect to to my RCOS rotator. The Observatory window is set up to use the RCOS TIM ASCOM Rotator driver. Until last night, connecting via the ASCOM driver has not been a problem.

When I click on the Rotator Connect button the Disconnect button briefly, very briefly, flashes active and then goes back to grey. No error message or anything. I've checked the setup including the COM setting, everything seems normal.

Has anyone experienced this type of connection problem using MaxIm?

Is there some way to troubleshoot the ASCOM driver/connection?

Is there a log I can take a look at?

Some background:
I have a 14.5" RCOS with a TIM controller mounted on a Paramount MEII. My image train is consists of an AO-X/STXL FWG-8/STXL 11002M.

The RCOS came with the factory installed rotator and focuser both of which can be directly controlled via the TIM controller software. Each can also be connected, via ASCOM, to other software such as MaxIm (usually) or ACP or TheSkyX, both of which continue to connect without fail.

My MEII is connecting to the MaxIm Observatory window with no problem. More importantly, the RCOS focuser, using the RCOS TIM ASCOM Focuser driver, is also connecting, no problem. Just the rotator is not connecting.

Generally, I'm using this setup with ACP Scheduler and have had, and still have, no problems connecting to the rotator.

This past few days I've been working on troubleshooting my AO guiding using only MaxIm, no ACP. Using MaxIm alone means I have to connect the mount, focuser and rotator directly to MaxIm through the Observatory window. When using ACP I do not connect to the MaxIm Observatory.

I also generally open and connect to the TIM controller program so I can run the fans and heaters. I've tried it both ways, with and without, but no rotator connection.

If anyone has any suggestions I'm all ears.
Thanks,

[Bob Denny]

This past few days I've been working on troubleshooting my AO guiding using only MaxIm, no ACP. Using MaxIm alone means I have to connect the mount, focuser and rotator directly to MaxIm through the Observatory window. When using ACP I do not connect to the MaxIm Observatory.

I can't imagine what would be causing this as long as MaxIm is the only program trying to use the Rotator at that time (ACP is not running right?). But I will say that trying to solve rotated AO guiding problems with nothing but the rotator raw angle and calibrating the AO manually in MaxIm, then looking at the ReverseX, ReverseY, and Swap Axes buttons, and trying to divine what is happening, is a prescription for confusion and eventual insanity :-) The offset between the mechanical rotation angle and the sky Position Angle, plus the rotational offset of the guide camera within the off-axis pickoff tube, add up to potential confusion.

Did this ever work in ACP, all sky, all PA, both sides of the meridian, without ever having to recalibrate the AO drive?

[Dan Simpson]

Hi Bob,
Thanks for the note. Colin at Diffraction sent me a copy of a Registry Editor file (RCOS PIR ASCOM (win64)) to edit the Registration Entries. It seemed to work, I'm again able to connect to the rotator via the MDL Observatory window. I'll check further under dark skies.

I have had some success using both ACP and just MaxIm (alone) but the guiding results have not been consistent. I might get a few shots with decent to very good guiding but there are way too many where the guiding leaves me with streaked unusable results.

After working with Daniel at Software Bisque I've improved the tracking on my MEII both mechanically and via new PEC and TPoint models. I can take 5 and even 10 minute images with very little drift. I think the most important lesson I've learned was - with good tracking - I'm able to slow down my corrections (1-2 second exposures) and that can minimize the tendency to chase the seeing. It seems to be working but, as a test, I thought I should also go back to just using MaxIm for guiding to ensure I have that part of the equation dialed in as well. Thus my need to have MaxIm connect to the rotator. I need to be certain the mount is able to manage the guiding consistently and at all angles using MaxIm alone. After that I can add ACP back into the mix and see where that takes me.
Take Care,

[Bob Denny]

OK, thanks for letting me know. Best wishes going forward.