Lens flange back adjustment

If images are not clearly focused at both telephoto and wide-angle positions during zoom operations, adjust the lens flange back (distance from the lens mounting surface to the image formation surface).

Once adjusted, the lens flange back does not need to be readjusted until the lens is changed.

For a normal lens

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Mount the lens on the camera.

Make sure to connect the lens cable.

Set the lens aperture to manual, and fully open the iris.

Place the lens flange back adjustment chart approximately 3 m from the lens and adjust the lighting on the chart to obtain an appropriate image output level.

If the image level is too high, use the filters or the shutter.

Loosen the F.f (Flange focus) ring clamping screw.

Set the zoom ring to the telephoto end position, either manually or by electric drive.

Aim the lens at the lens flange back adjustment chart and turn the distance ring to bring the chart into focus.

Set the zoom ring to the wide-angle end position and turn the F.f (Flange focus) ring to bring into focus.

At this time, do not move the distance ring.

Repeat steps 5 to 7 until the lens is in focus at both the telephoto and wide-angle positions.

Firmly tighten the F.f (Flange focus) ring clamping screw.

For an auto-focus compatible lens

If an auto-focus compatible lens is used, perform the following procedure to operate zoom and focus automatically and adjust the lens flange back.

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Mount the lens on the camera.

Turn the <POWER> switch of the camera to <OFF> before mounting the lens.

Make sure to connect the lens cable.

Set the lens iris to manual, and fully open the iris.

Place the lens flange back adjustment chart approximately 3 m away from the lens and adjust the lighting on the chart to obtain an appropriate image output level.

Do not place other subjects near the adjustment chart.

Set the <ZOOM> switch of the lens to the <SERVO> side. (Electric zoom mode)

Change the setting menu of the camera to adjust the lens flange back.

Select [EXECUTE] in the main menu → [MAINTENANCE] → [LENS ADJ.] → [FB ADJ.].

Select [YES] using the jog dial button, and then press the jog dial button.

The [ACTIVE...] message is displayed on the viewfinder screen during the adjustment.

The [FB ADJ. OK!] message is displayed on the viewfinder screen when the adjustment has completed.

The [FB ADJ. ERROR!] message is displayed on the viewfinder screen when the adjustment has not been performed correctly. In such a case, check the conditions of the subject and lighting, open the iris again, and perform adjustment again.