Bright Field Focusing - Honeywell PENTAX SPOTMATIC IIa Operating Manual

Hide thumbs Also See for PENTAX SPOTMATIC IIa:
Table of Contents

Advertisement

Bright field focusing
1 You can start viewing and focusing
before and after cocking the rapid
wind lever. When the preview lever
is in "AUTO" (automatic) position,
and the meter is at "OFF", the dia¬
phragm is fully open except for the
moment of exposure.
2
Turn the distance scale ring until
your subject image is clearly in focus.
It is not always necessary for you to
view and focus with the diaphragm
fully open.
In bright sunlight, you
can easily
focus with diaphragm
closed to f/5.6 or f/8 and still ob¬
serve the depth of field. It is easi¬
er, however, to focus with the dia¬
phragm fully open as your subject
image is much brighter.
When the letters "MAN" appears
beside the lever, the lens is in manual
position; when "AUTO" appears, it
is in automatic position.
Microprism
Honeywell Pentax cameras have a
Fresnel lens with a microprism cen¬
ter underneath the ground glass. As
you look through the finder, you will
see that the Fresnel lens consists of
many concentric rings which provide
the brightest possible image on the
ground glass.
The microprism is the center por¬
tion of this diaphragm. When your
subject is in focus, the image in the
microprism will be sharp and per¬
fectly clear.
If your subject is not
in focus, the microprism will break
the image up into many small dots,
much like an engraver's screen. You
can focus your subject on any por¬
tion of the ground glass.
11

Advertisement

Table of Contents
loading

Table of Contents