Here's the procedure I use to focus the Raspberry Pi 12MP HQ Camera. In this example I am using the Arducam 2.8-12mm C-mount lens.
|12MP HQ Camera|
|Arducam 2.8-12mm Lens|
Initial Focus Procedure
|HQ Camera attached directly to a Raspberry Pi case using a mini ball head.|
4) Being careful to not unscrew the lens, the C-CS adapter or the back focus ring; adjust the lens focus to the "FAR" setting.
|"raspistill -t 0" streaming to a monitor|
7) As you watch the screen, slowly unscrew the back focus ring until you get a sharp image. Then the assembly is aligned for the FAR focus setting.
|HQ Camera assembly|