Noted, I can switch channels to accomplish this but I am worried about the lens of IMX519 as I will need to switch between channel 0/1/2/3 every 1 second.
Can you confirm that:
You can’t focus each camera while in four in one mode.
You can switch between camera and do focus i2cset -y I2CBUS 0xc 0x0 SAVED_VALUE Then i2cset -y I2CBUS 0xc 0x1 SAVED_VALUE. SAVED_VALUE is the known value with maximum sharpness. There is risk of straining the lens over time if you switch between camera and do focus
Noted that Arducam recommend four camera focus on places at the same distance.
From where I see it:
Four-channel mode can work but the rescaling done by UC-512 maybe an issue (the image will be too small)
Single-channel mode can work but the focus will be based on 1 camera instead of each camera have it’s own focus value.
There is risk of straining the lens over time if you switch between camera and do focus
From what I see the steps that I need to do if we go with the single-channel mode and switch between camera:
Turn on the C++ app
Do autofocus for each camera and find the value with maximum sharpness.
loop every 1/4 seconds:
Switch to cam0 and call focuser.set(value), value which have maximum sharpness for cam0.
Switch to cam1 and call focuser.set(value).
Since this use motorized lens, I believe this will strain the camera. Other option is to follow your advice to focus on places at the same distance and to skip calling focuser.set(value) everytime we switch camera.