Sony SAL135F28 Service Manual page 7

1-5-2. Focus Trouble
Function NG
Check the distance
scale tube, focus ring,
fixed sleeve, and
2 group move
frame block.
NG
Replace the defective part
or apply the grease.
NG
Check the operation
again.
OK
SAL135F28 (STF 2.8(T4.5)/135) (135mm F2.8 [T4.5] STF)
Focus trouble
OK
Adjust the position of contact
piece of brush (for focus ring),
or replacethe brush
(for focus ring).
Clean the pattern of the
main flexible unit.
1-4
Position NG
Check the position of
contact piece and
NG
deformation of terminal
of brush
(for focus ring).
OK
NG
Check pattern
of the main flexible unit.
OK
Replace the
main flexible unit.
Perform the focus
brush position
adjustment and
pattern check.
(See page 4-33.)
OK
END
NG