An interpositive, intermediate positive, IP or master positive is an orange-based
motion picture
A film also called a movie, motion picture, moving picture, picture, photoplay or (slang) flick is a work of visual art that simulates experiences and otherwise communicates ideas, stories, perceptions, feelings, beauty, or atmosphere ...
film
A film also called a movie, motion picture, moving picture, picture, photoplay or (slang) flick is a work of visual art that simulates experiences and otherwise communicates ideas, stories, perceptions, feelings, beauty, or atmospher ...
with a positive image made from the
edited
Editing is the process of selecting and preparing written, photographic, visual, audible, or cinematic material used by a person or an entity to convey a message or information. The editing process can involve correction, condensation, org ...
camera negative. The orange base provides special color characteristics that allow more accurate color reproduction than if the IP had a clear base like an exhibition positive.
Description
From a traditional photographic perspective, an interpositive (short for ''intermediate positive'') is the negative image of the original camera negative, which is an intermediate step towards creating the
positive (exhibition) print.
The camera negative is projected onto negative film stock in a liquid environment - termed a
wet gate - where the film stock is exposed using a
contact
Contact may refer to:
Interaction Physical interaction
* Contact (geology), a common geological feature
* Contact lens or contact, a lens placed on the eye
* Contact sport, a sport in which players make contact with other players or objects
* C ...
process, so creating a like image (in effect, retaining the image in its negative -- i.e. "reversed" -- form) on negative film stock, as an intermediate step.
The interpositive historically had only one purpose, namely to be the element which is used to make the
internegative
An internegative is a motion picture film duplicate. It is the color counterpart to an interpositive, in which a low-contrast color image is used as the positive between an original camera negative and a duplicate negative.
After a film is shot, ...
.
The interpositive is made after the
answer print has been approved. All
lights and opticals from the answer print are repeated when striking the interpositive, and once the IP exists the original negative can be vaulted.
It is sometimes referred to as a "protection IP", since the only time the IP is touched is on the occasion of making the first or a replacement internegative. Since interpositives are used so rarely, they are usually the element that is in the best condition of all the film elements.
Interpositives are usually the element of choice for film-to-tape transfers:
# They are usually in better physical condition than the other film elements. The original camera negative is typically checkerboarded on several rolls, or may be chemically unstable if stored improperly.
# They are very low-contrast and therefore help to preserve shadow detail.
# Scratches or dirt on the IP appear as black defects on the transfer, which are generally less objectionable than white defects, which would be the case if the camera negative or internegative were used.
Photographers who create photographic art by ''
contact printing
A contact print is a photographic image produced from film; sometimes from a film negative, and sometimes from a film positive or paper negative. In a darkroom an exposed and developed piece of film or photographic paper is placed emulsion s ...
'', such as Platinum or AZO, need interpositives in order to create large negatives. The final artwork has the size of the contact negative produced. Interpositives are also the best means of archiving or copying old image libraries. Reversal B&W processing can also be achieved from an interpositive by means of various kits and published recipes.
See also
*
Bleach bypass
Bleach bypass, also known as skip bleach or silver retention, is a chemical effect which entails either the partial or complete skipping of the bleaching function during the processing of a color film. By doing this, the silver is retained in t ...
References
Film and video technology
Cinematography
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