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[telfish]

I have finished a conversion and need confirmation of my settings.

My mounts RA and DEC worm wheels have 180 teeth.
I have a driven pulley with 16 teeth and also a 16 teeth pulley on the worm gear.

My settings motor step angle 1.8
Motor gear ratio 1
Worm gear ratio 180

I am running a MKS gen L and amusing the Ramps 1.4 as the board as I can't find a firmware for the MKS. I am using TMC2100 drivers with all links closed, uStep gear change is disabled and Motor microstep level is set to 16..

Can anyone confirm these are the right settings, everything seems to be working fine though the mount does not seem to slew quite to the target. Am checking this the next clear night.

Running firmware v8.14

Thanks   Terry

[TCWORLD]

Hi Terry,

The settings look correct.

If you slew from one star to another and then back again, does it end up in the same place? If so, it could be as simple as a mount alignment issue that can be corrected by EQMODs N-Star alignment.

Also when doing sidereal tracking, does it follow a star? You could also try this during the day by timing one revolution of the worm - should in your case be 86164.0905/180 = 478.7 seconds. That would mean watching the mount spin slowly over the course of 8 minutes.

If however it doesn't get back to the same place, it is most likely an issue with the stepper motor skipping steps. This could be because the current setting isn't properly adjusted, or could be that you are slewing too fast for the torque rating of the motors. You could try slewing slow (setting the GoTo Rate to a lower value) and see if accuracy returns.

[telfish]

Thanks Tom.

I am a few days from first light, At the moment I am just eyeballing it pointing toward the Sun. Thanks for the confirmation my settings seem right. I have 84 ounce steppers on the scope so there should be plenty of torque, though I am running them at 12 volts. Will see how it works under the stars and maybe up it to 24 Volts as the MK will take that.

[telfish]

Finally got the CGE out under the stars for a short session (clouds) and it slewed close to the target, close enough for plate solving.  Tracking seemed OK.  Had issues with PHD calibration with west movements small or even moving backwards! and all others way too big.

Quick question. Do I have to configure a custom mount in Eqmod for the mount putting in all the settings  or can I just use the EQ6 settings.

[TCWORLD]

You don't need a custom mount in EQMOD - it will read the mount configuration information directly from the AstroEQ.

If tracking and slew are fine, then your configuration is correct. Tracking is quite obviously out when the settings are wrong


I presume you can slew the mount in all four directions? Curious as to why PHD would move in the wrong direction. It's possible that you need to increase the length of the guide pulses and possibly multiplication factor - I think this is a setting in EQMOD once you expand the window. One of the settings has options for x0.25, x0.5, x0.75, etc. Can't remember off the top of my head.

[telfish]

Thanks Tom.

I  found out that the mount is slewing and tracking at single steps and is not microstepping. Not sure how  to get the MKS board to microstep with the 2100 drivers so I am going to go back to the 8825 drivers which I believe microstep at 32 with no modifications to the board.

Has anyone got the MKS board to work with the 2100 and if so how?

As to setting microstepping. If I want say 32 microsteps which is all links on the board set will Astroeq then do the gear change. Or do I need to set at 1 step all links off and Astroeq will set microstepping in software?

I think the PHD issue may be striction in the west direction that is stopping a full movement per step. I will loosen things up a bit on the worm and see how it goes. I am close but no cigar yet.

Regards

Terry