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The Ilmifs or range wnhin which a stereopfoffing
instrument is capable of operating. For example,
the rnuttii)ax can adjust (or accommodate] for
smell fibs in the projectors ranging fmm
approximately 10° about the x-axis to 20” ebout
the yexis.
MIL-HDBK-850
accumsslatod dlscropmrcy-The algebreic
sum of the aarparssfediiepenciee which occur in
the various sleps 01 Maklnc! a survey or of the
computa!kxr of a survey.
accumulated dhrergenca-(leveling) The
algebraic sum of the rtiva~nces for the sactiirse
of a MIS of levels, tmm me ba@nning of the tine
to any section end a! which If Is deslmsf to
@mPWe the total divergence.
accumulative error—Sae ayatematlc
error.
eccurecy checkln@—The procurement of
presumpfiwe evidence of a map’s wrnpliance
with specified accuracy sfanderds. Accuracy
cheddng generally indicates fhe relative (rather
than the absolula) accuracy 01 map Iaatures.
accuracy evaluation—The comparison of the
quaihy of an MC&G producl with meintenake
criteria to ascertain ifs adequacy with respecl to
its intendad use.
accuracy mathod-The method used in
determining the staled aocuracy ot s produci.
The melhod can range from a system empfoying
highly sophisticated tachnlquea to a highly
subjective )udgment, and IS essential for proper
use of the stated accuracy.
accuracy revlow-The comparison of an
exlstlng MC&G preducl against source material
or data more accurate lhan that from which H
was produced, for the purpose of determining
the accuracy of its horizontal and verfiial values.
accuracy teatlng—The procurement of
corrflnmad evidence, on a sarnpting basis, of a
map’s Co@lance wifh specified accuracy
srandards Accvrecy tasfing Is designed to
indkate both the relafive and absolute accuracy
of map feeturas.
accuracy—1. The degree of conforrnit y with a
standard, or tha degree of parlecfion atfalnad In
a maasuramam. Afxuracy ralafee to the quallty
“@a KEJdt, Srnd IS tLSW’I@Sht3d lrOM precisbn,
which relates to the quelily of tha Op.SratlOn by
which tha resuil k obtained end can be
repeatti. 2. The ctoseness of the besf
eefimeled value obtainad by fhe rnaaeuremente
to Ihe %ue- value of the quamity meaeured.
accurate contour—A contour line, the
accuracy of which ties within one-half of the basic
vertical inlewal. Atao called normal contour.
ecetata-A nonflammable plaatic ahaeli~
uaad as a besa for photograph!! films or as e
drafting base for overlays where Crnlcal
registration Is not required.
achromatic color-Cobr that does not etiiif
hue.
achromatic larta-A lens that has been parfly
corrected for chromatic aberration. Such a Iana is
usually of a mutli-elemem design to bring green
and red Iighl rays to approximately the same
polm of focus.
acoua!lc navigation-blavlgation by means of
sound waves whether or not they are wiihin the
audible range. Also called aonlc navigation.
See also Dopplar sonar navigation.
acthrlc Ilght+ighl which is capabla of causing
pholochemical cha~es in a sensitized emuision.
acflve $atalllt-A saleltite which transmits an
electromagnetic signal. A satelliie with the
capability to transmit, repeat, or retransmit
electromagnetic information, Sae also pasahra
aatalitta.
actlva tracklno ayatem—A satellite tracking
system which operates by transmission of signals
to and receipt of responses from fhe safelfite.
actual error—The dMerence between !he true
value and the measured value of a physical
quanf ity.
acutanca-An Oblecfive measure of [ha ablfiiy
of e photographic system to show a sharp edge
between comiguous areas of low and hiih
illuminance.
acfap!atlon-The facufry of fhe human eye to
adjust its sensitivity to varying Immensitiesof
illumination.
aedftlve color mixture- Super- Impoafflon or
other nondestructive cortrbhation of Iiiht of
dHferant chromaticlfies.
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