Grundig GCI-F0505B, Руководство пользователя

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19. Back Focus Adjustment
When to adjust the back focus:
Back Focus refers to the distance from the rear lens element to the camera focal plane. It is only required to
adjust the back focus only when the focus cannot be adjusted throughout its zoom range.
Requirements:
Tools required when carrying out back focus adjustment include:
1. Test chart / contrasting object
2. Allen Key (depending on the camera model)
How to adjust the back focus:
Step 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). Please loosen the Back Focus Retaining Screw by hand or with the supplied Allen Key (depending on
the camera model).
Step 2: Make sure the iris is wide open. Therefore, it is advised to keep the environment in low light condition. To
open the automatic lens completely, please use a neutral density filter. With this filter it is possible to simulate a
low light condition so that the lens can open up completely.
Step 3: Adjust the focus to in fi nite far ( ∞ ).
Step 4: Turn the zoom to the wide angle position, and then focus with the back focus adjustment on the test
chart.
Step 5: Set the zoom now to the most extreme telephoto position.
Step 6: Focus on the object with the focus screw of the lens (not with the back focus adjustment!). If this
procedure is successful, the back focus adjustment is finished and you can continue with step 8. If it was not
successful, please carry on with Step 7.
Step 7: Repeat steps 3 ~ 6 until the focus can be adjusted throughout the zoom range. When using a zoom lens,
the focus does not need to be adjusted again once the back focus adjustment has been completed. This does not
apply to vario lenses.
Step 8: Tighten the back focus ring’s retaining screw to fi x the back focus adjustment.
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