(SANITIZED) 1540 SPLIT-FORMAT LIGHT TABLE (PROTOTYPE)

• Document Type: CREST
• Collection: NGA Records (Formerly NIMA)
• Document Number (FOIA) /ESDN (CREST): CIA-RDP78B04770A002200040023-0
• Release Decision: RIPPUB
• Original Classification: S
• Document Page Count: 4
• Document Creation Date: December 28, 2016
• Document Release Date: December 1, 2006
• Sequence Number: 23
• Publication Date: January 16, 1969
• Content Type: MF

ed For~elease 20~~~~'1~`~C~~~SE~IA-R?P78B04770A002200d
 Approved For Release 2006i1~~~~
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~~ DP78B04770A002200040023-0
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IAS~TA 269
16 January 1969
MII~iIORANDUM FOR: Chief, TSSG~NPIC
DED~TSSG
15+0 Split-Format Light Table (prototype)
25X1
25X1
1. We a reciate bein invited to participate in discussions
at the on 10 January 1969 concerning the sub- 25X1
ject R contract. In return we are listing below our comments on
the specific items which were considered.
2. POWER-ASSISTED HAND CRANK MECHANISM (mock-up was available
for inspection
a. Advantages
(1) Hand crank conveniently located near the operator.
(2) Film did not spill off supply spool when hand crank-
ing was stopped.
(3) No objectional noise was apparent.
b. Disadvantages
(1) Precise positioning of a particular image area
(under a microscope rhomboid, for example) world probably be quite
difficult. The hand crank operated almost completely free of drag
and the film coasted after movement of the hand crank was stopped-
requiring movement of the crank in the opposite direction to stop
the film.
(2) The null position of the motor drive knob- (located
adjacent to the hand crank) varies with the amount of film on the
take-up and supply spools. It must be readjusted when operation of
the hand crank (or the motor drive) ceases, in order to keep the
film from creeping. (Broadening of the null position could reduce
this disadvantage somewhat.)
(3) The proposed hand crank mechanism will not provide
the film movement capabilities specified in NPIC's development
objectives for the 15+0 light table, i.e., drive two parallel rolls
of film in the same, or opposite, directions with the same hand
crank.
Although the mock-up hand crank mechanism seemed to
operate satisfactorily, it appeared to offer no advantages not
already available in the motor drive system. Both provide a con-
GRtiuPt venient method of moving film across the light table at various
Ettcladed frem aator~atic
dc.~radradin~ and -
declassific