e_hd250.book Page 51 Tuesday, October 24, 2006 3:11 PM
Back Focus Adjustment
It is only necessary to perform this when the lens is attached for the first time or when focusing is not correct in both the telephoto and
•It is easier to adjust back focus when the subject is more than 3 meters from the camera.
The optimal subject for this adjustment is a Siemens star chart.
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1.Set the IRIS mode switch to M (Manual).
2.Set the zoom mode to M (Manual).
3.Open the iris by turning the iris ring.
If the illumination is too strong, reduce it or move to a darker place.
4.Turn the zoom lever until the lens is at the maximum tele- photo position.
5.Bring the subject into focus.
6.Set the lens to maximum
7.Loosen the back focus ring retaining knob.
8.View the same subject and adjust the back focus ring for the best possible focus.
9.Repeat steps 4. through 8. about three times for fine adjustment until the subject remains in focus in both the telephoto position and the
10.Tighten the back focus ring retaining knob to secure the ring.
1
2 7, 8, 10
Siemens star chart
51