PHOTOGRAMMETRIC ENGINEERING
13
9 inch by 18 inch picture area can be
tested.
The large test camera, shown in
Figure 5, was manufactured by Con
solidated Photo Engravers, Equip
ment Company, and was designed
primarily for testing special long
focal length reconnaissance and spot
ting lenses. It is over 20 feet tall and
will accommodate lenses up to 100
inches in focal length and 16 inches
in diameter. The collimator for this
camera is placed on a swinging mount
Fig. 4. Medium size lens test camera. ^ ^ foot deep pit under the cam
era. The operator rides in the small
elevator on the left.
Figure 6 shows the folded collimator which is mounted in the pit. The angu
lar positions of this collimator can be set by remote control from the operator’s
elevator. The collimator is shown without its cover. This arrangement makes
possible testing these heavy lenses in a vertical position, and large cameras in
any oblique position. Considerable time and expense of flying large aircraft has
been reduced by means of this apparatus.
Figure 7 is a picture of the plate holder carriage and control panel. For
focusing, the plate holder carriage is moved by a slow-motion electric drive.
Focus positions are read to the nearest .1 mm. from a scale mounted on the
rear of the camera. A magnified view of the scale and vernier is projected for
convenient reading by the operator.
This camera will accommodate either
plates or film up to 40 inches in
length.
All the testing in the laboratory is
done in accordance with MIL-STD-
150. This document may be of con
siderable interest. It can be obtained
from the U. S. Government Printing
Office. Instead of being the work of
any one organization, it represents
the combined thinking of many lead
ers in the field of photographic optics
such as Dr. Gardner, Dr. Pestrecov,
Dr. Baker, Dr. Washer, Dr. Hop
kins, Dr. Scott, Mr. Cox, Paul Foote,
Mr. Kingslake and many others. It
was very pleasing to work with these
men in the preparation of this docu
ment which has already proved its
value in preparing specifications and
standardizing test procedures for
aerial lenses. It is hoped that the
recently adopted specification of Fig. 5. Large test camera designed primarily
Commission I of the International f or testing special long focal length reconnais-
Society of Photogrammetry will prove sance and spotting lenses.