Sony FE 70-200 mm f/ 2.8 GM OSS Lens Guia Do Utilizador
4-16
SAL75300 (4.5-5.6/75-300) (75-300mm F4.5-5.6)
4-5.
FOCUS-SHIFT CHECK/ADJUSTMENT
This section describes the check/adjustment of focus-shift amount resulting change of focal-length by zooming.
4-5-1. Focus-shift Check
Equipment
• 1000 mm Collimator
• Flange Back Tester
• A-mount Attachment
• Flange Back Gauge (43.50mm)
1. Preparations
1)
Perform “1. Preparations” of “4-4-1. Flange Back (f’F) Check”.
2. Checking Method
1)
Check the flange back (f’F) at each focal length (75, 200 and 300 mm) by turning the zoom ring of the checking lens.
Note:
The focus-shift amount of the checking lens is difference between the maximum flange back (f’F) and minimum flange back
(f’F) at each focal length.
Focus-shift = Maximum flange back (f’F) reading - Minimum flange back (f’F) reading
Specification range: 0.1 mm
2)
When the focus-shift amount is over the specification range, perform “4-5-2. Focus-shift Adjustment”.