b. Location. Mounted on the back support plate of
2-13. Copyboard Fine Adjustment Handwheel
the camera back.
a. Description. The copyboard fine adjustment
c. Purpose.
Controls the movement of the
control is a handwheel (9, fig. 1-4) approximately 7
lensboard distance to and from the focusing glass.
inches in diameter, and is pinned to an extension which
Control use for approximating distance only.
connects it to the copyboard drivescrew.
b. Location. On the camera back on the same
horizontal plane as the drivescrew.
2-9. Lens Vertical Control Knob.
c. Purpose. Provides the fine adjustment of the
a. Description. The vertical movement of the lens
copyboard in moving it to and from the focusing glass
is controlled by a finger-grooved knob (5, fig.
after an approximation has been made with the
4), being pinned to a shaft extension with the
copyboard control switch.
lensboard control shaft operating through it.
b. Location On the back support plate of the
camera back.
2-14. Counter Safety Lights and Switch
c. Purpose. Governs the vertical movement of the
a. Description. The copyboard and lensboard
lens by raising or lowering the inner lensboard frame.
positioning counters are equipped with shielded safety
This movement results in a vertical displacement of
lamps (9, fig. 4-1) on the darkroom side of the camera
the photographic image on the focusing glass as may be
back. The counters are provided with one switch,
required for centering, positioning, or measuring the
controlling the lamps on the camera back.
vertical dimension of the image.
b. Location. Mounted inside the counter platform.
c. Purpose. Provide illumination of the counters
under darkroom conditions.
2-10. Lens Horizontal Control Knob.
a. Description. The lens horizontal control knob
2-15. Vacuum Back Valve Handle
(10, fig. 1-4) is identical in physical appearance as the
a. Description. The vacuum back valve handle
lens vertical control knob, having gripping qualities on its
(13, fig. 1-4) is an indicator lever, controlling the vacuum
circumference.
area of the vacuum back.
b. Location. On the back support plate of the
b. Location. Mounted on the vacuum back valve
camera back.
housing, centered about the indented digits.
c. Purpose. Governs the horizontal movement of
c. Purpose. Regulates the air intake through the
the lens on the lensboard. This movement displaces the
vacuum back, controlling the suction area of the porous
photographic image on the focusing glass horizontally as
plate for various negative sizes.
may be required for centering, measurement, or
positioning the horizontal dimension of the image.
2-16. Camera Crank Handle
a. Description. The camera crank handle (7, fig.
2-11. Lensboard Fine Adjustment Handwheel
1) is a steel hand crank broached with a square opening
a. Description. The lensboard fine adjustment
to engage the top end of the jack screw shaft on the
control is a solid-metal handwheel (7, fig. 1-4)
copyboard end of the camera.
approximately 7 inches in diameter, pinned to an
b. Location. A loose item, carried in the toolbox.
extension which connects it to the lensboard drivescrew.
c. Purpose. To elevate the camera on its skid for
b. Location. On the camera back on the same
installation and to lower it into compact form for
horizontal plane as the drivescrew.
transportation.
c. Purpose. Provides the fine adjustment of the
lensboard in moving it to and from the focusing glass
2-17. Magnetic Contactor
after an approximation has been made with the
a. Description. The magnetic contactor (4, fig. 17)
lensboard control switch.
is a two-pole across-the-line type automatic starter used
in the arc lamp circuit of the camera.
2-12. Copyboard Control Switch
b. Location. Mounted on the rear support plate of
a. Description. The copyboard control switch (I11,
the truss support assembly.
c. Purpose. To transmit the heavy current load
copyboard through the copyboard drive motor. The
required by the arc lamps without requiring this current
switch is provided with a hand lever, spring loaded,
to pass through the control switches.
which returns to a neutral position after being released.
b. Location. On the back support plate of the
2-18. Vacuum Back Pushbutton Switch
camera back.
a. Description. This vacuum back switch (6, fig.
c. Purpose.
Controls the movement of the
copyboard distance to and from the focusing glass.
the vacuum back turbo-compressor assembly.
This control is used for approximating distance only.
b. Location. Mounted on the back support plate of
the camera back.
2-9
