1 - NGA

MIL.HDBK-850
process of p+cfing a tiffed or obfii
photograph onto a horizontal reference plane.
lAlf~h the process kr applied -My to
aerial photographs, il may also ba applii 10 the
correction of map daformalion.] Sea also
●talytlcal ortont.stlon; ●mplrlcal
orlontatlon; graphical ractlflcatlon;
multlplo-sksgo rectlficatlon: optical
rectification; p=per-sttlp method; polntmalchlng
method; transformation.
roctlfled ●ltItuda-Saa eppmsnt ●ltitude.
rectified prhrt-A phetogra@r in whiih tilt
dspkrcemant has been removed from the
original negative, and witiih has bean brwghf
to 8 daaiiad scale.
rcdifiar-A apacially daaignad proj-ion
printar wtrosa gaomatry is variable in order to
aiimlna!a till from an aerial nagativa. There are
fwe basii IYPSY those in whch tfra optical axis
of the racfifiir lens is the mmrnon ralerance or
base diredbn of the instrument, and those in
whiih the line batwean the Princ@le point of the
negative and the rectifier lane is the common
reference. Also called cutomatic rectiflw
ponoutom~t Ice .wtif!er; nontiltlng- lens
4“ “ ‘“”‘-iectlfler; nontlltlng-nogatlve- plane
mctlfler; rectifying camera; tilting-lens
rectlfler. See alae autofocus rectifier:
transforming printer.
mctlfylng camOra-See rectifier.
rectifying latituda-The tatifude on e sphere
such that a great circle on if has the same
length sc a meridiin on tha spheroid and such
that all lengths along e maridkm frem the
Equator are exactly equal to the cerraspending
Iangfhs on tfra Wheroid. Rectifying Mtude is an
atmihy latitude used in prcislerns of geodesy
and Canography.
mctlfylng printer—See rectifier.
rectilinear coordlnatoa—Sea rectangular
coordlrrataa.
mctobllqum plotter-See ●ngulator.
rectoplanlgraph-An instrument utilizing e
vertical photograph mounted in a verlical
pcdth, and used in the preparation of
planimatric maps.
red Ilght madabls ma~A map printed with
epeciel inks vhiih can be read under condiIiona
Z13
requiring E@CXASI fighting e.g., in a tank or
aircnsfl during rtightfkntr oparatbna.
red magnetlarn-The megnetiarn of the
north-seeking and of a freely auapwwW
magna. This is the magnetism of ths Earth’a
south megnafic pole. see also blue
ntegnetlsm.
reduced gmvlfy~rvsrd gravity that has
trwn reduced to the gaoid or to some other
rafarence surface by one c4 the gravily
reductions.
reduced latltuda-Se e parametric
latitude.
reduction factor—Sea scale of
reproduction.
reduction printer—See diaposltlvo
printer.
raductlon to ●lllpsold-l%e correction
aubtrackl fmm or addad to the maaaurad
horizontal length d a Iina at avaraga
topographic elavatien to mduca & to the
ccmrastmndhg length on the pertinent etfii.
Tha haighI used in Ihlc raducthn vAtl dtier by
the amount of the gaoid heighf from the hdght
mad in reduction to saa Iavel.
reduction to sea level—A reduction applied
to a measured horizontal ferrgfh on ltra Earth’s
surface to radma it to the surface of the focal
aaa level datum.
reduction to the merldlan—l%e procaee of
aPPfYm9 a ~r-tbn to an aftftude O&XSCWVad
tien a body IS near the celeet”kd maridiin of Ihe
Mraarvar, to find the al!ifuda at maridiin tranah.
The allilude at the time c4 such en cbaarvation
is called an ●xmerldlan altltudo.
reduction-to-contor-l. The emeunt which
must be appiiad to e dwacticur ebaervad al an
-ntric statien or to an =Cantrb signet, to
raduce such dtractien to what it would be if there
were no such sccentricii. 2. (aafronemy) One of
the values used in finding Ihe equation of time.
reference datunr-A general term applhd to
any datum, plane, er surface usad as m
reference or base frrrm wtriih other quantiiiaa
can be measured.
reference dlrectlon—A direction uaad as a