12 
OPTICAL AND SENSITOMETRIC DEVELOPMENTS 
RESOLVING POWER TEST TARGET 
USAF • 1951 
Fig. 2. Latest U. S. Air Force Target. 
evaluate this work. Figure 2 is the latest U. S. Air Force target, manufactured 
by the Buckbee Mears Company. It is a modification of the standard three line, 
high contrast target which has been used in laboratory tests for approximately 
14 years. 
Consideration should also be given to some of the photographic test equip 
ment recently acquired by the Air Force. In Figure 3 is pictured the visual 
test bench and one of the 16 inch diameter 14 foot Fecker collimators. The lens 
holder on this bench was designed for rather large aerial lenses and has 6 degrees 
of freedom. The collimator is a Wright-Schmidt design, with the target placed 
on axis by means of a beam splitter 
plate, so that no occulting area exists 
in the collimator beam. 
Figure 4 shows the medium size 
lens test camera. The collimator tube 
is to the right. This camera was manu 
factured by the Jam Handy Corpora 
tion and has all the necessary adjust 
ments for making through-focus 
exposures at any field angle out to 45 
degrees in increments of lj degrees. 
The angles are being calibrated for 
distortion measurements. The stand 
ard plate holders take either film or 
plates 2 inches by 14 inches and, with FiG. 3. Visual test bench and a 16 inch diameter 
a special adapter, lenses covering a 14 foot Fecker collimator.