Canon EF 200-400mm f4L IS USM Extender 1.4x - Manual (Page 19)

ENG-18
12. Hood
The special hood that comes with this lens cuts
out unwanted light and protects the front of the
lens from rain, snow, and dust.
To attach the hood, loosen the hood lock knob
by turning it counterclockwise. Fit the hood onto
the lens’s hood mount, and tighten the lock knob
to fix it in place. Use the same procedure, in
reverse, to remove the hood.
11. Infinity Compensation
Mark
For accurate focusing in MF on subjects at infinity
distance, look through the viewfinder or at the
camera’s LCD display while rotating the focusing
ring.
To compensate for shifting of the infinity focus
point that results from changes in temperature.
The infinity position at normal temperature is the
point at which the vertical line of the distance
scale L mark is aligned with the distance index.
Infinity compensation mark
Distance index
Lock knob
COP
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