Distance from home to PWM for auto Zoom

Hi all, developers.
I have a 30x zoom camera on my tracker. It zooms from PWM 1ms to 2ms Unfortunately not proportional. I.e. 1.5ms no zoom. <1.3 Zoom out, >1.8 zoom in.

Is there any way to run a script in the APM to to a 1ms pwm for 10 seconds on start up to zoom right out. Then something like for every 50m distance 2ms for 1 second to zoom in a bit. and likewise in revere.

I have not pulled the camera to bits yet but it may be possible to add a pot to the zoom ring to make it proportional, well at least feedback for the APM. in this case it would run like the tracker in motor mode rather then servo mode but using the pot rather than the IMU.

Any ideas or guidance would be most appreciated.

Regards
Anthony

Hi Anthony,
I intent to add a 3rd axis on Antenna tracker for the same reason (follow with a calera + zoom)
=> before i start i would like to know if you finally have progressed ?
That’s been a long time ago i know ;o)
François