Canon EOS 55 Service Manual page 146

When using a tool lens with a focus vari-
ation label reading other than 0.00 pro-
ceed as follows.
Select F4 Defocus Data Output on the
AF menu screen to display the screen
shown at the right. Tum the focusing
ring of the lens from the infinity end
while observing the DEFOCUS indica-
tion. Stop the focusing ring when the
DEFOCUS indication reaches a value
which is equal to and which has an
opposite sign to the variation marked on
the tool lens. (See that GAIN is set to L.)
When the focusing ring is overturned, be
sure to set it back to the infinity end and
then tum
it
again.
(Example) When the defocus is +0.03,
stop the focusing ring when the DEFO-
CUS indication reaches -0.03.
5) Press the Return key to return to the AF
menu screen.
6) Press the F2 AF Focus Adjustment and
repeat steps 1) through 4) to make AF
focus adjustment again.
3-55
AFDEF
I
Defocus da:ta
I
outpt
Left (13)
00. 00
Part 3: Repair Information
CV(Ll)
00. 00
CH(L2)
00. 00
Right (L4)
00. 00
Press RETURN to AF MENU screen.