Page:Glossary of NPIC Terminology (1965).pdf/14

Rh of the original subject. The plate or film does not become a negative until it is ex- posed. ' nitrocellulose section -— That part of an ex- plosives plant where wood or cotton pulp is nitrated with nitric acid to form nitrocellu— lose. ' nitroglycerine section —- That part of an ex— plosives plant in which glycerine compounds are nitrated to form nitroglycerine. no apparent change (NAC) -- The physical as— pects of a target, as imaged on the‘photog— raphy in question, appear to be essentially the same as on prior coverage 'of the target. nonpersistent agent —— A volatile chemical agent which forms a cloud and dissipates rapidly into the atmosphere. (chemical warfare)

obliquity (O) 4— That condition in which the opti— cal axis of the camera is tilted appreciably from the vertical, often limiting detailed analysis.

offshore wharf —— A structure built parallel to the shore and connected to it by l or more narrow approaches or gangways. Vessels berth along its face. A ‘

orthostereoscopy —— A condition wherein the horizontal and vertical distances in a stereo— scopic model appear to be at the same scale.

partial target coverage —- See target coverage. persistent agent -— A nonvolatilmmical agent

which remains on the terrain or on clothing in the form of droplets. (chemical warfare)

and equipment

photo base —— l. The length of the air base as defined on the photograph. (mensuration) 2. The accumulation of photocoverage over a target area for the express purpose of creating a comparative file in relation to prospective cover. ' ‘

NPIC/R-282/65

Photographic Evaluation Report (PER) -- A technical publication expressing the photo quality results of a mission of photography. Emphasis is placed on the negative aspects of the results to guide those concerned in applying appropriate corrections.

Photographic Intelligence Listing -— A list of photographic reports produced or received by the National Photographic Interpretation Center; it' is in 3 parts and lists the re- ports by originator, by general subject, and alphabetically. ~.

photographic quality —- A result of the camera system, processing; and film handling. Good photographic quality encompasses all the criteria for good image quality with the ex— Ception of unavoidable degradations not as- sociated with the taking system, i.e., at- mospherics, snow cover, etc.

photographic resolution —- A measure of the smallest array of point objects distinguish- able as independent point images, frequently expressed in lines per millimeter, where "line" refers to the distance between centers of two distinguishable point images. '

pier —— A wharf extending perpendicularly or .obliquely into the water with aCCommodations for 'ships on both sides; it may be straight, T—shaped or L-shap'ed.

pilot's trace —- An annotated overlay or map compiled with the assistance of the pilot of a photographic mission. It may containvthe fol-

, lowing information: ground track of the recon- naissance aircraft; camera designation;.loca— tion of camera operation; indicated altitudes at specified checkpoints; recorded times at specified checkpoints; and estimated cloud cover observed along the flight line.

‘plot 4— An overlay or map depicting the geo—

graphic coverage of a photographic mission. poor interpretability —- See interpretability. positive —- A photograph having the same