What’s back focus?

Back focus is the distance from final point of lens to the focal plane (camera’s image sensor). If the back focus is out of focus, it will be out of focus too.

The distance (camera flange back) from the C mount of the camera to the image sensor surface may be slightly different depending on the camera. Therefore, when changing the lens or camera, it is necessary to adjust the back focus.

(We combine the camera and the lens. Our company has shipped after adjustment carefully)

In case of lens with back focus adjustment mechanism, you can also adjust by yourself.

At our company we also sell lens with back focus adjustment mechanism as option lens.


Lens with back focus mechanism


Please contact for more information.