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Precautions, Mounting and Cleaning (Basler Lenses)#

Read the information in this topic carefully before mounting and using the lens.


WARNING – Eye Injury Hazard

Do not look at the sun or other strong light sources through the lens. This may cause injury to the eyes.

NOTICE – Inappropriate use may damage the lens.
  • Do not place the lens under direct sunlight. This may cause fire.
  • Do not disassemble or modify the lens. This may impair the performance of the lens.
  • The lens is not intended for use in environments where strong vibrations can occur.

Mounting the Lenses#

C-Mount Lenses#

  1. Align the lens thread with the camera mount thread.
  2. Screw in the lens until it is firmly attached to the camera.


If you want to use the lens with a CS-mount camera, attach a 5-mm distance ring (non-threaded for C125 5M series) to the lens. To find a suitable distance ring, visit the Basler website or contact Basler technical support.

F-Mount Lenses#

  • To install the lens, insert the base of the lens into the mount and turn the lens counterclockwise until it locks in place.
  • To remove the lens, press the lens release button on the camera mount and turn the lens clockwise.

Adjusting the Iris and Focus#

To adjust the iris and focus:

  1. Make sure that all locking screws (thumbscrew and grub screws) are not fully tightened. There are screw holes at different positions available.
  2. Rotate the iris ring or the focus ring of the lens to adjust the iris or focus.
    If available, align the white dot on the iris ring with the orange dot on the lens barrel to get the optimum aperture setting.
  3. To secure the iris ring or focus ring, tighten all locking screws (thumbscrew and grub screws) with a maximum torque of 2 Ncm.

Attaching the Filter#


  • To remove dust from the lens, brush off the dust with an oil-free soft brush or a lens blower brush.
  • To remove water or oil from the lens:
    1. Wipe away the liquid with dry lens cleaning tissue.
    2. Moisten the lens cleaning tissue with lens cleaning liquid.
    3. Wipe the lens gently with the moistened lens cleaning tissue, starting in the center and moving outwards in a circular motion.