Adjusting the Back Focus
Back Focus refers to the distance from the rear lens element to the camera
focal plane. In most cases, it is required to adjust back focus only when the
camera’s lens cannot hold focus throughout its zoom range.
► To adjust the back focus
1. Set the camera on a stable mount, with the test chart or object at least 75
feet (23 meters) away (or as far as possible).
2. Make sure the iris is wide open. Therefore, it is advised to keep the
environment in low light condition.
3. Adjust the focus to infinite far (∞).
4. Turn the zoom to the extreme telephoto position, and then focus on the
subject.
5. Set the zoom to wide-angle position.
6. Loosen the back focus ring’s retaining screw with the supplied adjuster, and
adjust the back focus ring for sharp picture.
7. Repeat steps 3 ~ 6 until focus can stay the same throughout the zoom
range.
8. Tighten the back focus ring’s retaining screw to fix the ring.
Chapter 1: Nextiva V4320 Series Overview
© 2014 Verint Systems Inc. All Rights Reserved Worldwide.
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