Canon EF 28-300mm f3.5-5.6L IS USM - Manual (Page 11)

ENG-10
8. Infinity Compensation Mark
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 L mark is
aligned with the distance indicator on the
distance scale.
The infrared index corrects the focus setting
when using monochrome infrared film. Focus on
the subject manually, then adjust the distance
setting by moving the focusing ring to the
corresponding infrared index mark.
The intermediate markers between 300 and 100
are 200mm and 135mm, and the marker
between 100 and 50 is 70mm.
9. Infrared Index
• The infrared index position is based on a
wavelength of 800 nm.
• The compensation amount differs depending on
the focal length. Use the indicated focal length as
a guide when setting the compensation amount.
• Be sure to observe the manufacturer’s
instructions when using infrared film.
• Use a red filter when you take the picture.
Some EOS cameras cannot use infrared film. See
the instructions for your EOS camera.
For accurate manual focusing on subjects at infinity
distance, look through the viewfinder while rotating
the focusing ring.
Infinity Compensation Mark
Distance index
COP
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