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Adjusting the Lens Flange
When images are not clearly focused at both the telephoto and wide-angle positions during zoom
operations, adjust the flange back (the distance from the lens mounting surface to the image
formation surface).
Once adjusted, the flange back does not need to be readjusted as long as the lens is not changed.
Adjustment method
Check the position of each part of the lens which must be operated in order to adjust the flange
back with the lens Handling Instructions.
Adjusting the Flange Back
1Set the lens iris to manual.
2Open the iris. Position the flange back adjustment chart about 10ft (3 m) from the lens and
illuminate it so that an appropriate image output level is obtained.
Use the filter and/or shutter if the video level is too high.
3Loosen the Ff ring clamping screw.
4Set the zoom ring to the telephoto position manually or by electric drive.
5Shoot the flange back adjustment chart and turn the distance ring to bring the chart into focus.
6Set the zoom ring to the wide-angle position.
7Turn the Ff ring to bring the chart into focus.
At this time, take care not to move the distance ring.
8Repeat this operation four to seven times until the lens is in focus at both the telephoto and
wide-angle positions.
9Firmly tighten the Ff ring clamping screw.
ÁRefer to the Operating Instructions of the lens.
Approx. 10ft (3 m)