Canon A-1 - Manual (Page 124)

c a t e a n e x p o s u r e a d ju s tm e n t o f o n l y 1 / 3
f / s t o p , b u t y o u r p i c tu r e w il l b e e x p o s e d i n
t h e 1 / 3 f / s t o p i n c r e m e n t y o u s e t o n th e d i a l.
Generally, exposure should be corrected
whenever the high-key (light) or low-key
area occupies more than half of the total
viewing area. How much more or less ex­
posure should be given depends on the light­
ing condition as roughly described, below.
However, these are only general guidelines
meant to help you while experimenting.
S o m e situations require special measures.
For instance, when shooting a subject a-
gainst the sun or some other exceptionally
strong light source, requiring drastic ex­
posure correction, or when you shoot a
subject in an unvarying lighting condition
such as under photolamps in a studio, it
may be better to use the exposure memory
switch as explained on the next page or
manual override.
The exposure compensation dial can also be
used to correct exposure in multiple ex­
posures as explained later.
Usable Range of Exposure Compensation
Dail According to ASA Rating
ASA6;
ASA12: 1 / 4 - - 1 / 2 - - 1
1 / 4 - - 1 / 2 - - 1 - - 2
ASA25-3200: 1/4* • 1/2 • • 1 • - 2 - - 4
ASA6400:
ASA 12800:
1 / 2 - - 1 - - 2 - - 4
1 - - 2 - - 4
Once you have made an exposure correction
on a specific frame using the exposure com­
pensation dial, do not forget to reset the dial
to its original setting. Otherwise, all follow­
ing frames will be incorrectly exposed.
Scale Exposure Correction
1/4 2 f/stops underexposure
1/2 1 f/stop underexposure
i Normal
2 1 f/stop overexposure
4 2 f/stops overexposure
Application
Black background
Spot lighting
Black background occupying half of viewing area
Overhead interior lighting
Subject by a window
Blue sky or sea backgrounds occupying half of viewing area
Contre-jour portrait, white background, snow
scene or blue sky background____________________________
-
70
-