24 
APPLICATIONS OF VARIABLE CONTRAST PAPERS 
from either single or double frame 35 mm. negatives or from 70 mm. or 5-inch 
camera negatives. The small box sitting on the right side of the printer has five 
push buttons which are numbered to correspond with five different filters which 
are inserted automatically in the printer light path when the button is depressed. 
In the production versions of this printer the push buttons will be located on 
the right hand panel. Contrast control is thus achieved by the operator as he 
/. VOLTAGE control 
2 VOLTAGE CO/VTROL 
J. VOLTAGE CONTROL 
4 VOLTAGE C O/VTROL 
s. EEC AD/A'G COUNTER 
6. POWER SW/TCM 
7. P/L Ai L OCR 
e. START PR/A/T/MS SW/TCW 
9. VAR/SAM E/L TER COMTROL 
/0. T/MER 
//. OOEG/A/S PAMEL TRAMS PER 
ARM 
Fig. 6. USAF Type D-1 Contact Printer. 
views each negative before setting into the printer the number of prints desired 
and starting the printing operation. The paper capacity of the E-1 is 9§" X1,000- 
foot rolls. 
One type of variable contrast paper, “Varigam” has been available to service 
organizations in limited quantities for the past two years. Considering that it 
could be used only on the 5-Type cut- 
sheet projection printers, the effect on 
field units has been only one of famil 
iarization and training. Extensive 
field tests on the experimental D and 
E type printers have been in progress 
for one year using two different types 
of variable contrast emulsions coated 
on water-resistant base. The second 
type is an experimental paper sub 
mitted by the Eastman Kodak Com 
pany for evaluation. The main ob 
jectives of these tests are: 
1. To evaluate relative merits of 
conventional graded papers and 
variable contrast papers. 
2. To determine the type of variable 
contrast paper best suited to aeri 
al reconnaissance photography. 
3. To develop satisfactory means of 
contrast control on roll-type 
printers. 
Fig. 7. USAF Type £-1 Projection Printer.