Setting The Asa Film Speed - Canon A-1 Instructions Manual

Setting t he ASA
Film
Speed
The ASA is a numerical rating of a film's
sensitivity to light. The higher the ASA
rating, the faster the film and the more
sensitive it is to a given amount of light as
compared
to a
fi lm
of a
lower ASA rating.
In
other words, the higher the ASA rating, the
less light you need to expose the
film.
\Vhen
buy ing film, choose one wi th an ASA rating
appropriate for the lighting conditions. The
film manufa cturer's recommended ASA
rating can be found on the film packaging or
data sheet.
Since the ASA film speed is one of the
essen tial factors in deter mining proper ex-
posure, it is very important that it be
correctly set on the camera. The table on the
opposite page shows the ASA ratings which
can be set on the A -1 . Figures in parentheses
arc intermediate film speeds which are
in-
dica ted
by
dots on the ASA dial. To se t the
- 28-
ASA , press in the ASA film speed dial lock
button with your fingernail an d turn the
outer knurled edge of the dial until the
desired film speed rating is aligned with
the film speed index. T he dial cannot be
turned
lower
than ASA 6
or
higher than
ASA 12800.
The!'e is an exposu re compensation scale on
the
ASA
film speed setting dial. The fu nc-
tion of this scale will be explained later, but
at this point, please note t hat this scale
should be set at " 1" for normal AE pho-
tography.