Note For Adjusting Focus And Zoom - GeoVision GV-BX110D User Manual

Note for Adjusting Focus and
Zoom
When adjusting the Focus and Zoom Screws (on Box Camera, Bullet
Camera, Vandal Proof IP Dome and Fixed IP Camera), please do not over
tighten the Focus and Zoom screws. The screws only need to be as tight
as your finger can do it; don't bother using any tools to get them tighter.
Doing so can damage the structure of lens.
For example,
Bullet Camera Fixed IP Camera
The maximum torque value for all the zoom and focus screws is 3.9 to
4.9 N.cm
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