On my EOS M3 I have the option to control the aperture with CHDK.
With all Canon lenses I had the possibility to change them in 1/8EV steps. It was also possible with the Sigma ART 24mm.
Seems to be standard for lenses.
You can then perform smooth aperture ramping.

https://youtu.be/sETz7PhPMaI
https://youtu.be/nG2YqO0AFlE

So far I could only control the exposure time and ISO in 1/96EV steps.

https://youtu.be/dsEw2cKN9KQ

The fine adjustment offers me three advantages.
1) I have almost no flickering. So just need a simple workflow.
2) I can also change the exposure during a sunset without getting a pumping sun https://forum.lrtimelapse.com/Thread-pumpende-sonne
3) I also don't get flickering in Lightroom when I use non-linear tools (Dehaze, Clarity, Whites and Blacks). With my 6D, that's already happening.

So I can use CHDK to create a 3-way ramping “True Holy Grail” without a flicker via script.
As a basis I use this script
https://chdk.fandom.com/wiki/Lua/Scripts...rvalometer
The script works with a RAW histogram. This allows you to control the exposure very well.

Examples with the script:
Canon M3and EF-S 55-250 https://youtu.be/Cljd3Lzi21M
Canon G1x https://youtu.be/yF9PnmIcRQc