Pentax SF1 - Interchangeable Focusing Screens

INTERCHANGEABLE FOCUSING SCREENS
In addition to the standard all-surface-matte focusing
screen, two other optional screens are available. The
screens can easily be changed by using a pair of tweezers
included in the focusing screen's case.
Scale Matte Screen (FD-41):
for photomicrography and
macrophotography.
Cross-Lined Matte Screen
(FG-40): for copying work
and general-purpose
photography.
1. As illustrated, the focusing screen hangs down when
the pressure plate {behind the "O" mark) is pulled
down (toward an arrow "- ► " ) .
2. Take the screen out by grasping its projected part with
the tweezers and stand it up at the groove of the case
to avoid damages or scratches.
3. As illustrated, place the new screen on the frame
with the tweezers and push the frame up until it locks
with a click.
The focusing screens are made of plastic. Be careful not
to damage them when handling. To clean a screen, use
a blower to blow away the dust.