2. D850 Online Manual
3. Menu Guide
4. B The Setup Menu: Camera Setup
5. AF Fine-Tune

Fine-tune focus for up to 20 lens types. Use only as required; AF tuning is not recommended in most situations and may interfere with normal focus. Auto fine-tuning is available in live view (0 Auto AF Fine-Tuning). We recommend that you perform fine-tuning at a focus distance you use frequently; if you perform focus-tuning at a short focus distance, for example, you may find it less effective at longer distances.

AF fine-tune (On/Off)

• On: Turn AF tuning on.
• Off: Turn AF tuning off.

Saved value

Tune AF for the current lens (CPU lenses only). Press 1 to move focal point away from camera or 3 to move focal point toward camera; choose from values between +20 and –20. Values for up to 20 lens types can be stored. Only one value can be stored for each type of lens.

Current value

Previous value

Default

Choose the AF tuning value used when no previously saved value exists for the current lens (CPU lenses only).

List saved values

List previously saved AF tuning values. To delete a lens from the list, highlight the desired lens and press O (Q). To change a lens identifier (for example, to choose an identifier that is the same as the last two digits of the lens serial number to distinguish it from other lenses of the same type in light of the fact that Saved value can be used with only one lens of each type), highlight the desired lens and press 2. A menu will be displayed; press 1 or 3 to choose an identifier and press J to save changes and exit.

Auto AF Fine-Tuning

Auto AF fine-tuning is performed as described below.

1. Ready the camera.

   Mount the camera on a tripod and aim the camera at a flat, high-contrast subject parallel to the camera focal plane. Note that auto AF fine-tuning works best at maximum aperture and may not function in dark surroundings.

   

2. Start live view.

   Rotate the live view selector to C and press the a button.

   

3. Adjust focus settings.

   Rotate the focus-mode selector to AF and use the AF-mode button and command dials to select the following:

   • Autofocus mode: AF-S
   • AF-area mode: 5 (wide), 6 (normal), or 3 (pinpoint)

   

4. Select the center focus point.

   Press the center of the multi selector to select the center focus point.

   

5. Focus.

   Press the shutter-release button halfway to focus, then zoom in on the view through the lens to confirm that the subject is in focus. Focus can be adjusted manually if necessary.

6. Perform auto AF fine-tuning.

   Press the AF-mode and movie-record buttons simultaneously and keep them pressed until the dialog shown in Step 7 is displayed (this should take slightly over two seconds).

   

   AF-mode button

   

   Movie-record button

7. Save the new value.

   Highlight Yes and press J to add the AF fine-tuning value for the current lens to the saved values list (CPU lenses only). Note that only one value can be stored for each type of lens.

   

8. Enable AF fine-tuning.

   In the camera setup menu, select AF fine-tune > AF fine-tune (On/Off), then highlight On and press J.