Canon F1-N Film Camera User Manual


 
22 EXPOSURE COMPENSAT ION
Note
When it is difficult to determine exactly how much correction to make, bracket the
exposure. using any of the three methods.
4. ”Pushing” the ISO Rating
There may be occasions when, due to insufficient lighting, you are forced to use
undesirably slow shutter speeds. In this case, you can ”push” the ISO setting on
the camera to a higher value. Usually this is done by multiplying the normal ISO
film speed by a multiple of two, such as two or four. The entire roll of film must
be shot at the ”pushed” ISO setting; otherwise, exposure will not be correct for all
frames. It is also necessary to inform the developing lab of the change in the ISO
rating or the film will be incorrectly developed. Hbwever, since not all films can be
”pushed” with acceptable results, it is recommended to read the film data sheet or
other photographic literature before you try this technique.
49