Projective Resolving Power Check - Sony SEL90M28G Service Manual

4-5-2. Projective Resolving Power Check

Equipment and Tools
• Lens Test Projector (J-6082-778-A) and Variable Transformer (Output voltage: AC 100 V)
Note: Connect the variable transformer (Output voltage: AC 100 V) to the Lens Test Projector.
• Screen (Art paper)
• Tape measure
• Plane mirror (For SLRs)
(1) Checking Method
1. Perform "2. PROJECTIVE RESOLVING POWER CHECK" of "E-MOUNT LENS GENERAL ADJUSTMENT GUIDE".
Reference value:
Focal length f
Distance (m)
(mm)
Center (y' = 0)
More than
90 3.6
63 lines
2. Check the projective resolving power. If the projective resolving power does not satisfy the reference value, adjust the resolving power (partial
blur).
4-6. RESOLVING POWER (PARTIAL BLUR) ADJUSTMENT
1. Increase or decrease the thickness and number of adjustment washer A to adjust the partial blur.
Adjustment Washer A
Adjustment Washer A
1st GP Assy (9118)
Fig. 4-6-1
2. Perform the check and adjustment repeatedly until the partial blur is resolved.
Note: If the partial blur cannot be resolved even after the adjustment, replace the Optical Block For Service.
SEL90M28G (FE 2.8/90 MACRO G OSS) (FE 90mm F2.8 Macro G OSS)
Number of the smallest pitched (lines/mm)
Peripheral (y' = 15) Peripheral (y' = 18)
S M S
More than More than More than
32 lines 32 lines 20 lines
Table 4-5-1
4-4-1. Adjusting Procedure
Adjustment Washer A
Part No. Thickness t (mm)
4-464-741-01 0.03 ± 0.003
4-464-741-11 0.05 ± 0.005
4-464-741-21 0.075 ± 0.008
4-464-741-31 0.1 ± 0.008
Table 4-6-1
4-4-1. Adjusting Procedure
M
More than
20 lines
4-9E