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[almcl]

Well many thanks to Tom for very promptly sending me a replacement motor control board after I fried one of mine, and my AstroEQ is now up and running.  It slews the Skywatcher 200p around the sky at a mighty rate.  Unfortunately it hasn't so far managed to slew it in the right direction.

Not sure if this is an AstroEQ issue, my feeling is that it isn't as, when using the buttons on the Eqmod interface the scope appears to move in the right direction E/W and N/S.  However, when Cartes du Ciel takes over, it invariably ends up going north when I think it should be going south and ends up pointing at the ground.  I've tried reversing DEC, which changes the slew direction for the buttons but not when heading to a target.  I suspect its something I am doing (or not doing) in setting up the interface(s), but what.

My procedure (still on a steep learning curve with Eqmod & CDC) is to get the scope, after polar aligning and balancing, at the home position - pointing at the NCP - then connect up the mount to AstroEQ and launch CDC.  Then use the telescope control panel to connect scope, unpark it and then select a target in CDC (say Arcturus) and hit  slew on the menu. The scope sets off and either doesn't get anywhere near it or goes in completely the wrong direction and ends up pointing at the ground in a northerly direction.  I have tried swapping DEC and RA individually and together which doesn't seem to help.

If anybody can offer some advice, I'd be most grateful. 

[TCWORLD]

How did you reverse the DEC? Was it with the buttons in EQMOD or with the AstroEQ config utility? The reverse buttons in EQMOD don't actually do anything with AstroEQ, so you have to make the change in the config utility.

Tom.

[almcl]

I did wonder about that, I'll revisit the settings using only AstroEQ. 

[almcl]

And it's worked!  (Or at least it now appears to be pointing to the right part of the garage roof and to move in the right direction and by the right amount.)

Can't wait to try it out on some faint fuzzies.

Just need to get tracking with PHD2 sorted...

[TCWORLD]

I did try to figure out why the EQMOD axis reverse buttons don't work, but the best I can come up with is that AstroEQ is using the commands slightly differently to the Skywatcher mounts and there ends up being a double negative (EQMOD inverts two signals that end up cancelling out inside AstroEQ). Hence I added axis reverse options into the config utility.

Tom

[almcl]

Happy to report that it's working very nicely.

An Eqmod polar align was followed by 3-star align and then a slew to M13 (using Cartes du Ciel), which came up pretty well centred on the camera screen.  Followed in succession by M82 and M81.  Both came up dead centre on the camera.  M51 and M3 followed. 

Wow this almost feels like cheating, it's so easy! Amazing to see the target slide on to the screen and then move itself close to the centre.

Haven't sorted out guiding yet, PHD2 won't calibrate in DEC for some reason - a fairly poor calibration followed by taking the the guiding assistant's advice and it wouldn't move the mount in DEC at all.  Pretty sure this is a setting issue in PHD2, just not sure where...

[TCWORLD]

It may be a DEC backlash issue - in the guiding settings for EQMOD you can change the backlash correction and guiding speed. If you ramp the guide speed up to 0.9x it will clear through the backlash much faster and you should get calibration.

[almcl]

Thanks for that, Tom (yet again!)

Just checked and while the RA slider was at .50, the DEC one was at .1 (no idea why, haven't touched that bit of Eqmod), so have tried sliding it to.5 also.

With luck there will be a clear sky just after sunset this evening so will see if calibration can now take place.

[almcl]

Clear skies and adjusting the slider to .6 resulted in quite a good calibration. 

Lots of tweaking needed, I suspect, to get the best out of the system and probably some more fiddling to make sure DEC backlash is as small as possible, but Astroeq definitely working very nicely.