I think I’ve come to the same conclusion about the mount. I opened mine up and there’s only a small amount of backlash in the two metal gears connecting the motor/gearbox to the worm gear. There is much more movement in the shaft that enters the gearbox. Not just backlash, but the shaft itself wiggles a bit with only a small bit of force on it. I’m guessing that is the real source of my problem. That said, when I turn the motor shaft by hand (black plastic gear on the opposite side of the metal gears), there doesn’t seem to be a lot of backlash when I change directions. The metal gears and worm start turning within ~2/3 of a rotation. I don’t know how much movement that actually translates to however. It may be more than can reasonably be tolerated by the guider.
I did determine that what I thought was backlash in the RA axis was the shift of the tension mechanism holding the motor and worm gear to the main gear.
I’ll just have to give it a try with a better balanced setup and if necessary only guide in RA.
So I didn’t make any hardware adjustments, but gave things another go. I better balanced the DEC axis and got SM to calibrate and track once but not on any subsequent attempts. I then tried with PHD2 which does work - mostly. It is generally able to train and guide, though usually with at least one or more warnings about various issues it detected. It does guide and I finally can get longer exposures. I did have an issue on an auto-meridian flip as Ekos reported that guiding failed after the flip even though PHD2 was ultimately able to guide.
Thanks for the help everybody.
I have since decided a new mount is called for and have ordered a Rainbow Astro RST-135.
Did you find any solution to the guiding issues with the azgti? Tonight I tried guiding with the azgti and didn't get any acceptable result - neither in ekos nor in phd2... In phd2 I tried to measure the dec backlash. The backlash graph is showing a huge backlash in dec - phd stops measuring just when the backlash steps end and the reverse motion is beginning.
I did get good enough guiding using PHD2 for my setup (with just a WO RedCat 51 - so 250mm focal length). Make sure your setup is as balanced as possible. That combined with PHD2 let me at least get it to calibrate and guide. It may depend on the specific characteristics of your AZGTI though. In the end I had already ordered a Rainbow Astro RST-135, so I haven’t used the AZGTI since I got that.