Canon CN-E15.5-47mm T2.8 L S Operation Manual page 22

3
Turn the iris ring to set the iris to fully open (T2.8).
4
Turn the zoom ring to set the lens to the telephoto end,
then turn the focus ring to bring the object into focus.
5
Turn the zoom ring to
set the lens to the wide
angle end, then turn the
F.B. adjuster to bring the
object into focus.
Note: Be sure not to move the focus
ring at this time.
6
Repeat steps 4 and 5 two or three times.
7
Secure the F.B. adjuster and reattach the F.B. adjuster
cover following the reverse procedure.
F.B. adjuster
9
Use the index
mark and
adjuster scale
for back focus
adjustment.