007 - Microform (R)
MARC 21 Bibliographic - Concise
2007
Transparent or opaque medium bearing microimages that are too small to be read without
magnification. A microform may be an original publication or a reproduction of existing
textual or graphic material.
Character Positions00 - Category of material h - Microform
01 - Specific material designation Special class of microform to which the item belongs. (e.g., a microopaque).
a - Aperture card
b - Microfilm cartridge
c - Microfilm cassette
d - Microfilm reel
e - Microfiche
f - Microfiche cassette
g - Microopaque
u - Unspecified
z - OtherIncludes microforms such as microchips, microdots, and microform scrolls.
| - No attempt to code
02 - Undefined
Contains blank (#) or a fill character (|).
03 - Positive/negative aspect Positive/negative polarity of the microform.
a - PositiveLines and characters appear dark against a light background.
b - NegativeLines and characters appear light against a dark background.
m - Mixed polarityMixture of positive and negative images.
u - Unknown
| - No attempt to code
04 - Dimensions Dimensions of the microform; does not indicate the dimensions of the
image.
a - 8 mm.
d - 16 mm.
f - 35 mm.
g - 70 mm.
h - 105 mm.
l - 3x5 in. or 8x13 cm.
m - 4x6 in. or 11x15 cm.
o - 6x9 in. or 16x23 cm.
p - 3 1/4 x 7 3/8 in. or 9x19 cm.
u - Unknown
z - Other
| - No attempt to code
05 - Reduction ratio range Reduction ratio range for a microform. The specific reduction ratio is recorded in
007/06-08 (Reduction ratio).
a - Low reduction ratioLess than 16:1 ratio (less than 016).
b - Normal reductionBetween 16:1 and 30:1 (016-030).
c - High reductionBetween 31:1 and 60:1 (031-060).
d - Very high reductionBetween 61:1 and 90:1 (061-090).
e - Ultra high reductionOver 90:1 (over 090).
u - Unknown
v - Reduction rate varies
| - No attempt to code
06-08 - Reduction ratio Number specifying the reduction ratio for a microform, recorded as three digits.
The number is right justified and each unused position contains a zero (e.g., 015,
048). A hyphen is used for any unknown portion of the reduction ratio (e.g., 03-,
1--, or ---).
09 - Color Color of the image for microforms.
b - Black-and-whiteIncludes only one color or hue other than black, for example, blue-and-white
(blue-and-transparent). Always used for microopaques.
c - Multicolored
m - Mixed
u - Unknown
z - Other
| - No attempt to code
10 - Emulsion on film Type of light-sensitive material on the film.
a - Silver halide
b - Diazo
c - Vesicular
m - Mixed emulsion
n - Not applicableUsed for microopaques.
u - Unknown
z - Other
| - No attempt to code
11 - Generation Generation aspect of a microform.
a - First generation (master)Camera master or COM recorder master.
b - Printing masterAny generation employed mainly for the production of other microforms.
c - Service copyMicroform made from another microform that is intended primarily for use rather
than for production of other microforms. Always used for microopaques.
m - Mixed generation
u - Unknown
| - No attempt to code
12 - Base of film Base of the film.
a - Safety base, undetermined
c - Safety base, acetate undetermined
d - Safety base, diacetate
i - Nitrate base
m - Mixed base (nitrate and safety)
n - Not applicableMicroform on a reflective rather than a transparent base.
p - Safety base, polyester
r - Safety base, mixedMixed safety base films are spliced together; no nitrate film.
t - Safety base, triacetate
u - Unknown
z - Other
| - No attempt to code