Pentax 6x7 Manual page 16

When infrared film is used , the focus of a lens
differs somewhat from the norm, and varying degrees
of compensation are required which differ from lens
to lens. The depth-of-field scale of each 67 lens
includes an infrared index mark for focusing with
infrared film .
When using infrared film, first, focus in the normal
manner ; then, check the distance figure aligned with
the standard index mark of the focusing ring . Com -
pensate for infrared shooting by rotating the focus-
ing ring until this figure is realigned with the infrared
index mark. For example, if the distance scale is set
at
00
(infinity) turn the infinity mark so that it aligns
with the infrared index as shown in the illustration
above the photo .
• Always use an R2 or an 02 filter for infrared
photography.
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