26
Adjusting the lens flange
If the subject is not focused properly in the telephoto
and wide-angle modes during zoom operations, adjust
the flange back (distance from the lens mounting
surface to the image-forming surface).
Once this adjustment is done, it need not be redone
unless the lens is replaced.
Adjustment method
1
Attach the lens to the camera.
At this stage, do not forget to connect the lens
cable.
2
Set the lens aperture to manual and open the
aperture.
3
Set the lighting in such a way that the appropriate
video output level is achieved at a distance of
about 3 meters away from the chart used for the
flange back adjustment.
If the video level is too high, use the filters and
shutter.
4
Loosen the screw securing the F.f (flange focus)
ring.
<Note>
On some lenses, this may be marked as F.b
(flange back) ring.
5
Set the zoom ring to the telephoto position either
manually or electrically.
6
Shoot the chart used for the flange back
adjustment, and turn the distance ring to adjust the
focus.
7
Set the zoom ring to the wide-angle position, and
turn the F.f ring to adjust the focus.
Take care not to move the distance ring during this
process.
9
Tighten the screw securing the F.f ring.
8
Repeat steps
5
to
7
until the focus is adjusted at
both the telephoto and wide-angle positions.
<Note>
For details on the adjustment method and lens
positions, refer also to the operating instructions that
accompany the lens.
Approx. 3
meters
