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Obtaining Parfocality Between Camera and Microscope Eyepieces

Setting your camera parfocal to your eyepieces will eliminate the need to refocus your camera’s image before each image capture, saving you time and frustration. The process takes only a few minutes to complete.

Method 1: Requires a microscope to camera adapter with focusing adjustment

  1. Adjust the distance between the eyepieces to match your eyes.

    Setting the microscope's interpupillary distance

  2. Set the eyepiece diopters to “0”, or… Optional Step 2: If you have a reticle in your eyepiece, adjust the eyepiece diopter so that the reticle comes into focus.

    Adjusting microscope diopters

  3. Place a sample on the stage and focus
    this sample using the eyepiece that is:

    • The eyepiece with the reticle
    • The fixed eyepiece/eyetube if only one
      diopter adjustment provided
    • The right eyepiece if both eyepieces
      have diopter adjustment

  4. Adjust the other eyepiece diopter until it comes into focus on the sample.

  5. Twist the parfocality adjustment on the optical adapter until the camera comes into focus. (Note: Parfocality locking screws may need
    to be loosened prior to adjustment and tightened after adjustment).

Method 2: Requires diopter adjustment on both eyepieces and the absence of any reticle or photo mask in the eyepieces

  1. Place a sample on the stage and
    focus it on the camera.

  2. Focus the right eyepiece diopter.

  3. Focus the left eyepiece diopter.

  4. Adjust the distance between the
    eyepieces to match your eyes.

Method 3: Requires back focus adjustment on the
camera

  1. Adjust the distance between the
    eyepieces to match your eyes.

    Setting the microscope's interpupillary distance

  2. Step 2: Set the eyepiece diopters to “0”, or…
    Optional Step 2 : If you have a reticle in your
    eyepiece, adjust the eyepiece diopter so that the reticle comes into focus.

    Adjusting microscope diopters

  3. Place a sample on the stage and focus this sample using the eyepiece that is:
    • The eyepiece with the reticle
    • The fixed eyepiece/eye-tube if only one diopter adjustment provided
    • The right eyepiece if both eyepieces have diopter adjustment

  4. Adjust the other eyepiece diopter until it comes into focus on the sample.

  5. Adjust the back focus of the camera by loosening the C-mount locking screws and turning the C-mount ring in or out until camera comes into focus on the specimen. Tighten the C-Mount locking screws.

    Adjusting the back focus of the camera

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