500/inch. This in fact is the major limitation of tne Electronic Rectifier.
Investigations indicate the present resolution capability can be doubled;
however, in doing so, other problems immediately come into view. Increasing
the resolution of scanning from 500 to 1000 lines/inch will deteriorate the
signal to noise ratio in the video channel and will utlimately reproduce
nosie in certain density ranges in the rectified photographe
The present equipment rectifies the unrestituted negative at a rate of
approximately 1 inch/min. This means it takes approximately 9 minutes to
rectify a 9 X 9 inch negative, Calculations indicate this can be impro ved
by a factor of 1, To achieve this, hwwever, requires scanning the negative
at 1000/min. This high scan rate causes excessive vibration and stress in
the scanning head which oscillates the scanning mirror, In addition exces=
sive vibration causes deterioration in the ULM output,
Regardless of the fore-mentioned limitations, the present equipment
has demonstrated exceedingly well, the practicality of rectifying tilted
photographs by flying spot scanning techniques. The accuracy of rectifi=
cation has been analyzed as well within that required for mapping. A new
Rome Air Development Center sponsored rectifier, differing in concept conside
erably from that just presented, is now in its initial design phase at the
Fairchild Corporation, This like its predecessor, the "lectronic Rectifier,
provides a major advancemen* in aerial rectification equipment, The instrue
ment will be completely universal in that is will accommodate panoramic
frame. and strip type photography, with greatly improved resolution and
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Spread through a number of years.