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

• Document Type: CREST
• Collection: NGA Records (Formerly NIMA)
• Document Number (FOIA) /ESDN (CREST): CIA-RDP78B04770A002200040025-8
• Release Decision: RIPPUB
• Original Classification: S
• Document Page Count: 3
• Document Creation Date: December 28, 2016
• Document Release Date: December 6, 2006
• Sequence Number: 25
• Publication Date: January 16, 1969
• Content Type: MF

SECRET
IAS/TA 2/69
16 January 1969
G.!i'l?itilE~ Etlq
MI 4ORANDUM FOR: Chief, TSSG/T FIC
?
DED/TSSG
1540 Split-Format Light Table (prototype)
1. We appreciate being invited to Participate in discuceions
at the on i0 January 1969 concerning the suE)-
ject R&D contract. In return we are listing below our comments on
the specific items which were considered.
2. Pte-ASSISTED HAND CRAM MECHANISM (mock-up was available
for inapeetion
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) 'Would 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 knoir (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' a development
objectives for the 1540 light table, i.e., drive two parallel rolls
of film in the same, or opposite, directions with the same hand
crank.
c. Conclusion
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-
venient method of moving film across thea.ig)Zt table at various
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speeds, but neither permit the fine positioning necessary to
align two images in stereo. For this reason, the combination of
a motor drive plus a mechanical crank (not motorized) mechanism
seems to be the most logical alternative.
3. MOTOii EI.WtFATING M HMSM (proposed.? mock-up not
available
a. Advantage
(1) Would permit the height of the table to be adjusted
without physical effort by the operator.
b. Disadvantage
(1) Would probably make the table more expensive.
(2) Would make the table more difficult and costly to
maintain.
Since, in lAS, elevating table heights,, once adjusted
by a particular user,, are seldom changed, a motorized elevating
c bility does not appear to be either desirable or cost-effective.
4. M RIZRD MICROSCOPE CABE.`[AGE (proposed by
no mock-up available)
a. Advantages
(1). Direction of movement controlled by a switch on the
microscope ring mount, thus the operator need not operate mechan-
ical X- handwheels for fine positioning as an the 9Z4o split-format
table.
(2) Speed would be adjustable to keep movement across the
field-of-view to about three seconds at any magnification. Manual
free movement of the carriage would also be possible when desired.
b. Disadvantages
(1 Possibility of vibration from the motors.
(2 Increased procurement and maintenance costs.
The desirability and cost-effectiveness of this capa-
bility appears doubtful.
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5. FIII4 SPOOL ALIGI'SEN' (proposed i 25X1
mock-up without visual referencing scale as avail
e e
The visual referencing scale described b-11
appeared to be adequate, but we believe a spring loaded detent
would be an improvement over the type which he demonstrated.
6. These comments are offered in the hope. they will aid
in developing a necessary exploitation tool whose sophistication
and cost will not inhibit its procurement in adequate quantities.
Tecjinicai Advisor, :#
Distribution:
Orig. - Addressee
1 -
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Approved For Release 20Q&12/06 : CIA-RDP78B04770A002200040025-8