Viewing And Focusing - Canon AT-1 Instructions Manual

Viewing and Focusing
Focusing
is
performed in the small round
area in the center of the viewfinder. The
smaller central circle is a split-image focusing
screen and around it i s the microprism ring.
The split-image rangefinder ascertains that the
image is "in focus" when the image divided
horizontally in half merges and becomes one
complete image.
The microprism rangefinder presents a
clear and steady image when in focus. The
microprism conveys a broken, shimmering
image when not accurately in focus. It
i s
also
possible t o focus with the matte screen
outside the smaller central area. You can
focus with any of these focusing aids a s you
like, depending on the subject and your pre-
ference.
Accessories such as an eyecup, dioptric
adjustment lenses, angle finders, and magnifier
can be attached t o the viewfinder eyepiece.
Out of Focus In Focus