007 - Microform (R)
MARC 21 Bibliographic - Concise
2009
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.
When field 007/00 contains code h, it contains special coded
information about the physical characteristics of microform
material.
Character Positions
00 - 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
h - Microfilm slip
j - Microfilm roll
u - Unspecified
z - Other
Includes microforms such as microchips, microdots, and
microform scrolls.
| - No attempt to code
02 - Undefined
# - Undefined
Contains blank (#) or a fill character (|).
03 - Positive/negative aspect
Positive/negative polarity of the microform.
a - Positive
Lines and characters appear dark against a light
background.
b - Negative
Lines and characters appear light against a dark
background.
m - Mixed polarity
Mixture 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 ratio
Less than 16:1 ratio (less than 016).
b - Normal reduction
Between 16:1 and 30:1 (016-030).
c - High reduction
Between 31:1 and 60:1 (031-060).
d - Very high reduction
Between 61:1 and 90:1 (061-090).
e - Ultra high reduction
Over 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-white
Includes 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 applicable
Used 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 master
Any generation employed mainly for the production of
other microforms.
c - Service copy
Microform 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 applicable
Microform on a reflective rather than a transparent base.
p - Safety base, polyester
r - Safety base, mixed
Mixed safety base films are spliced together; no nitrate
film.
t - Safety base, triacetate
u - Unknown
z - Other
| - No attempt to code