I am experiencing some dithering failures with Ekos and PHD2 with my EQmod mount since I updated to Kstars 3.5.2 and PHD2 2.6.6. I continued to apply the next updates but thit did not help to resolve this issue. Currently I am using the latest Astroberry on a Raspberry Pi 4 with Kstars 3.5.4 and PHD2 2.6.10. All the devices are directly connected to the Rpi4 throught USB. The mount is connected to the RPi4 with a FTDI serial to USB adapter.
I made several tests on different targets using the Ekos scheduler with my EQ6 mount and the the INDI Mount Simulator. The problem occurs only with my EQ6 and the EQmod driver but not with the Mount Simulator, that why I am not sure if the issue is related to Ekos/INDI or PHD2. I attached the Ekos and PHD2 logs with verbose mode enabled. There is an intersting message in the PHD2 logs that says :
I searched on the INDI forum and on Google and I did not found anybody else reporting this problem. So maybe I am doing something wrong or maybe there is a bad setting somewhere in Ekos or the INDI Eqmod driver that is causing this issue. Any help or advice is appreciated.
The message "guider.cpp:831->No mount" is given in two case, mount not connected, or not calibrated.
For some reason, short before this error, PHD2 receive a request to clear the calibration, probably from Ekos:
16:40:47.169 00.102 2999734288 evsrv: cli 0x1420aa8 request: {"id":220,"jsonrpc":"2.0","method":"clear_calibration","params":["mount"]}
This is the reason for the error.
You must check in the Ekos configuration you not activate an option to reset the PHD2 calibration on some condition, this is not need with Eqmod.
I looks like you are right : in the Ekos Guiding module, under the Calibration tab, the option "Reset Guide Calibration after Each Mount Slew" was enabled in my setup. So i disabled it and now the dithering works fine as before.
Thanks for your help.