The decision to use microrecords must arise from a municipality's specific circumstances and needs. When considering a microfilm application, the municipality should carefully consider its current situation and information needs and its short- and long-term goals. The various information management strategies available to it will have a broad impact on the manner in which it conducts its business and the services it seeks to provide for its constituents.
As with any technology, microfilm is a tool and not a cure-all; microfilming will not solve systemic faults in an information management system. Poor filing, inadequate indexing, redundant copies, poor information flow or failure to dispose of obsolete materials will not disappear with the establishment of a microfilm program. Rather, the municipality will spend a large amount of money to create a miniaturized version of poorly filed, redundant, inadequately indexed obsolete records.
A technological implementation should not be considered until the existing information system has been examined and optimized. Only at this point will municipal officers be able to clearly identify what problems, if any, exist, and the areas in which a microrecords program can make for better management. In all cases, it should be remembered that an information management system cannot center solely around microfilm. Microfilm is only one component of a successful system that may include paper, magnetic tapes and disks, and optical data storage systems.
When considering a possible microfilm application, it important to be aware of both the advantages and disadvantages of the technology.
Storage space reductionis probably the attribute most frequently associated with the use of microfilm. Records reduced to microform occupy as little as 2% of the space required for the original paper documents. Vendors and other enthusiasts have interpreted this figure to mean that space savings of 98% could be realized through microfilming. Such a figure is unrealistic and ignores the fact that many records must be retained in hard copy even after they have been microfilmed, and that space freed by microreduction will need to be devoted to retrieval equipment such as reader/printers. It has been found that in applications where files are frequently referenced, such as insurance claims, the space savings were in the area of only 15%. Nevertheless, the space reduction afforded by microfilm can be substantial, particularly if the records being filmed are particularly bulky and not subject to frequent retrieval.
File integrity is another major benefit to be realized from microfilm. Once a file has been filmed, its constituent records are locked in place in the order and condition in which they were sent to the camera. Alteration of the file is difficult and the retention of a master film copy at an offsite location acts as a backup ensuring that any tampering will be detected. To this extent, the accuracy of filmed files and other records is greater than that of their paper counterparts that are subject to tampering and alteration. Of course, this very integrity precludes the use of microfilm for "live" records, that is, records that must, in the course of business, be regularly annotated or amended. Updating of entire files, however, can be accomplished through the use of jackets or computer assisted retrieval (CAR) indexing programs.
Security of information is perhaps the greatest benefit of a microfilm program. The most certain way to ensure the physical security of vital or archival information is to duplicate the source record and store a copy at a secure remote site. Although this is not feasible where large volumes of paper records are concerned, it can be quite efficient in the case of microforms. The security duplicate film provides a back-up should the office copy be damaged or destroyed, and is a control in the unlikely event that the office copy of somehow tampered with or otherwise called into question. Because magnetic media are inherently unstable, transfer to microfilm through a computer output microfilm (COM) application can secure the preservation of long-term information from a short-term medium. Where the original records are themselves of value, the use of microfilm can be substituted in use for the paper records, enhancing their longevity. If the microfilm is designed for long-term retention, the security copy must be on silver-type gel emulsion film and stored under strict security and environmental conditions to ensure preservation and continued usefulness.
Ease and speed of retrieval of microfilmed information are made possible by the reduction in size from the original source documents and by competent indexing systems. Miniaturized information can easily be stored in the working office and can be accessed in seconds rather than in minutes or hours needed for paper stored in file rooms or stored off site. Digital reader-printers allow the retrieved image to be directly faxed or emailed to an off-site recipient or distributed to one or more desktops over the network.
It may be difficult to cost-justify a microfilm conversion based on any one of these factors: cost savings result from a combination of benefits. Rapid retrieval, reduced on- and off-site storage costs, reduced storage equipment requirements, enhanced file and record security, and increased flexibility and productivity in office arrangement and information management can result in significant dollar savings.
User resistance is often one of the strongest factors acting against the success of a microfilm program. Some users simply cannot come to terms with not having a piece of paper before them. Other complaints are more substantive and should be dealt with either in the planning phase or during implementation. Indexing may be inadequate and information retrieval difficult or time consuming; the reader may be in a location that makes its use inconvenient; film quality may be poor and the records difficult to read; arrangement of records on film may make the film difficult to use; the display size, format or quality of the reader may cause eye strain or fatigue in the user. Failure to address user problems can lower productivity and endanger the entire program.
Turnaround time can also limit the acceptability of microrecords. If records are unavailable for excessive periods of time during filming, the organization's operations may be adversely affected.
Startup costs are high, involving not merely filming of records, but creation of indexes, user training and the purchase and lease of equipment.
Legal acceptability of microfilm records is often of concern to custodians.
However, Massachusetts and Federal laws make ample provision for the use
of the medium. Chapter 66, Section 3 of the Massachusetts General Laws
establishes microfilm as an acceptable medium for the maintenance of public
records. The hearsay and best evidence rules are addressed by C.233 ss.79A,
79D and 79E of the General Laws. Section 79E is an acceptance of the Uniform
Photographic Copies of Business and Public Records Act that, along with
the Uniform Rules of Evidence, addresses these issues at the Federal level.
These laws make microphotographic copies of public records admissible
in evidence regardless of whether the original record is still extant.
To comply with these laws the microcopy must be:
Having determined: that the existing system is fundamentally sound; that implementation of other basic records management techniques will not solve existing problems or deliver the desired results; understanding the drawbacks and benefits of microfilm, the organization can conduct a feasibility study to determine the parameters of a microfilm program that can suit its needs.
The first step in the study is to examine the records that will be involved
in the program. A number of questions should be asked about the records:
The answers to these questions may decide whether special filming equipment or formats will be needed or whether the records should be microfilmed at all. Oversized, fragile or colored documents require special equipment, handling or photographic techniques. Frequently altered records need special indexing or perhaps ought not to be filmed at all. Except in the face of high security demands, it seldom makes sense to film small volumes of records that are seldom referred to, or, except when space is critical, records with short retention periods.
The answers to these questions will determine the type of microform to be used, the number of copies and the number and type of retrieval devices needed. The records may be used by office staff, auditors and other oversight personnel, researchers, the public at large or by all these groups. The level of usage will dictate the number of copies of film that must be made available and its potential location(s) (in-office only, in office and library, etc.). If several persons need access to records or files simultaneously, multiple copies of film or digitizing readers may be indicated. Similarly, if users are physically remote from the location of the records, it may be desirable to create duplicates to be sent to the user locations or to use digital reader-printers to transmit individual records on an as-needed basis. The needs of the user groups and the types of information they wish to extract from the records will also drive the type of indexing which will be required.
The answers to these questions
can begin to suggest possible costs for the program. File size and whether
the documents are double sided obviously will affect cost. Rate of accumulation
will determine how frequently or at what point the files must be filmed.
Staples, clips, double-sided documents, all mean more work and expense
in the document preparation stage.
The microform to be used will be determined by the characteristics of
the records to be filmed and film's intended use. There are a variety
of microforms available, some with very limited and specific applications;
for the purposes of this discussion, only five will be considered: roll
film, microfiche, film jackets, aperture cards and computer output microfilm.
The most common and least expensive microform is roll film. Available
in 16, 35 and 105mm widths, it is used for filming source documents or,
to a lesser extent, computer output. The film most commonly used for business
documents is 16mm. This film is available in a variety of lengths, most
commonly 100 or 215 feet, and may be as a loose roll or encased in a cartridge
or cassette. While the cassette format is nearly extinct, the cartridge
type of enclosure is very popular and can be accommodated by most readers;
it has the marked virtue of eliminating the tiresome fumbling associated
with threading the film into the reader and protects the film from damage
caused by handling. At the standard reduction ration of 1:24, a 100-foot
roll of 16mm film can contain 2,500-3,000 letter-sized pages, and a 215-foot
roll 5,400 or more pages.
35 and 105mm film are generally in loose rolls and are used for oversized
documents such as maps or engineering drawings, or for library or archival
applications. A 215-foot roll of 35mm film can contain 1,200 D-size drawings.
Because of the size variations of archival records, roll of film may contain
fewer documents at a considerably higher cost.
Records are filmed sequentially on roll film and once filmed are locked
in the order in which they went to the camera. Thisformat lends itself
to chronological or other sequential files and until recently was limited
to closed series which were not subject to updating. Computerized indexing
schemes now make it possible to film records out of sequence or add to
or integrate records in a filmed file. Each out-of-sequence record, however,
must be accessed separately and may even be on an entirely different roll
of film. This substantially slows information retrieval time.
Microfiche is a flat or unitized film piece produced from a roll of 105mm
film that is usually cut into 6-inch lengths. Fiche is generally produced
using a "step and repeat" camera or by copying from a microfilm
jacket and is a much costlier format to produce than is roll film. Fiche
lends itself especially to micropublishing, but is also used for other
applications such as checks, payroll and invoices. Cameras that produce
fiche generally can accept only individual documents. Although it is possible
to create fiche of bound volumes it is not recommended.
An index is often included directly on the fiche with documents located
on a horizontal/vertical grid. At the standard 24x reduction, a fiche
can contain 98 pages (14 horizontal by 7 vertical).
Fiche are identified by an eye-readable header across the top of the fiche.
This header may also be color-coded to facilitate filing. The size and
amount of information on a fiche makes it an ideal format for distribution
of data.
Microfilm jackets are polyester cards of the same 4x6 inch size as microfiche
with sealed channels created along their horizontal axes. Frames of developed
film are then "stuffed" into the channels. The channels may
accommodate 16 or 35mm film. Jackets are useful for subject-specific applications
where reference must be made to a particular individual or other subject.
A jacket may be configured to include 35mm film images of plans along
with 16mm images of specification sheets. They are easily updateable and
very simple to reference but do not provide the file integrity of roll
film or microfiche and are understandably more expensive.
A variant of the jacket is the jacket card. These are often preprinted
with specific information with channels to allow the addition of microfilm
to keep the file up to date.
Jackets are often copied to fiche for office use and distribution.
Aperture cards are standard-sized tab cards that accommodate developed
microfilm, usually a frame of 35mm film. Indexing information is typed
along a header or punched into the card itself for automated retrieval.
This format has its primary application in filming plans, drawings, maps
and blueprints.
Computer output microfilm (COM) is created through a process closely
related to electronic publishing. Information from a computer is converted
into an eye-readable form and imaged directly onto film. This process
is much faster and cheaper than standard technologies for printing to
paper. Some COM recorders allow the film to be imaged directly from internal
memory without having to create a separate tape. The COM film can then
be created on line.
COM may be in roll format but a fiche format is the most common. A standard
fiche of COM can contain 270 pages of computer printout at the standard
COM reduction ration of 48x.
Two variants of COM deserve note. These are computer input microfilm
(CIM) and documents scanned to microfilm. CIM is essentially an input
mode for optical character recognition (OCR) systems. Text is recorded
on microfilm that can be then optically scanned, converted into ASCII
format and input into a computer system. Documents scanned to microfilm
are first optically scanned using a laser scanner, converted a format
that can drive a COM recorder, and then committed to film; this type of
film is usually used as a back-up for optical data storage systems.
Unless microfilm is to be used only as a security device, it will be necessary
to provide a reader or reader-printer to read the filmed documents. Readers
and reader-printers range from very simple devices for reading microfiche
to massive computer-linked robotic units that can automatically load film,
retrieve images and make multiple copies. The simplest and cheapest of
these machines is the microfiche reader. Roll film readers are considerably
more costly. Readers are available which are capable of accepting both
formats.
The choice of retrieval equipment will depend upon the type of film being
used in the office, its use and frequency of reference, and the need to
generate hard copy of the images. The convenience and comfort of users
should be a prime consideration in choosing the type of retrieval hardware
(and film format) which will be used. Inconvenience and discomfort associated
with microfilm use will decrease productivity, engender hostility among
researchers and endanger the program. If users are expected to spend a
considerable amount of time in front of the reader, it is important to
provide large screens with good illumination and contrast to minimize
eye strain. The readers should be provided with comfortable seating and
located in a comfortable area convenient to the employees' normal workstations.
Readers intended for retrieval of maps and plans should be equipped with
interchangeable or zoom lenses to allow the user to inspect details of
the images. If the readers are to be used by researchers, or if several
employees are expected to be accessing the records simultaneously, a sufficient
number of readers and film copies should be provided to minimize waiting
time and consequent reduced productivity and user dissatisfaction.
The public records laws apply to micro-images as well as to paper. If
a record is on film, a copy must be provided on request. A reader/printer
should be easily available to each office for this purpose.
There are a number of ways in which microfilm can be indexed. The choice
of indexing scheme is determined by the amount and type of records being
filmed, the anticipated frequency of retrieval, the use to which the retrieved
images will be put, and whether image retrieval is a time sensitive component
of office procedure.
The simplest form of indexing roll film is simply to label the box with
the contents and to use a combination of flash targetsand blank frames
like folder tabs and dividers in a conventional paper filing system to
separate the groups of images on the film. The user can consult a log
to identify the proper roll of film and then browse the roll until the
proper record group is located.
Roll film can be indexed by odometer reading, that is, by the number
of inches of film as indicated by a dial on the reader, or by sequentially
numbered frames on the roll. An image is then located by advancing the
film to the proper frame number or odometer "mileage." It may
also be indexed by blip coding. In this type of indexing, small patches
of constant size and density are recorded on the film as each document
is photographed. These "blips" can then be read by a photoelectric
cell either integral to the reader or available as an add-on. By recording
the documents as they are filmed an accurate index can be created with
each set of blips corresponding to a single document. The correct blip
code can be determined from the index and the reader set to advance the
film to the proper location.
Microfiche and jackets are identified by an eye-readable header across
the top of the unit. This header contains the important indexing data
for the images on the unit. The header may be color-coded and the units
arranged as they would be in a conventional filing system. Fiche may also
contain an internal index, usually located in the lower right-hand corner
indicating the location of a particular document on the vertical/horizontal
(numeric/alphabetic) grid.
Aperture cards are indexed in a similar manner. Additionally, indexing
information may be keypunched onto the card itself to allow for automated
retrieval.
These manual or semi-automated retrieval schemes can be successfully applied where the records involved are sequentially or otherwise logically arranged in closed series, and speed of access is not an important consideration. However, where records cannot be filmed in such a logical sequence or where rapid access or access by a complex combination of parameters is needed, these schemes cannot suit the needs of the organization. In these situations, a more sophisticated indexing scheme is needed, and this need is filled by a computer-assisted retrieval (CAR) system. Briefly stated, a CAR system involves on-line entry of index information to a database management system to create, maintain, retrieve and manipulate an electronic index to the locations of records on film. The index information may be linked to filmed record identifiers such as blips or bar codes, or may be text-associated. Sophisticated CAR systems can conduct Boolean searches and display microform addresses in complex relationships. A CAR system is necessary to any application that calls for integration of microfilm into an active information management system.
All microfilming of public records is governed by 950 CMR 39.00, Regulations on Using Microfilm. These regulations are designed to ensure that all public records are filmed in accordance with the industry standards specified by the American National Standards (ANSI) and the International Standards Organization (ISO), and that the quality and longevity of the film is equal to or greater than that of the original source documents.
Preparing documents for filming is the most time-consuming, labor intensive
part of the microfilm program. All files to be filmed must be carefully
inspected to ensure proper arrangement and that all unnecessary or redundant
material has been properly removed. Documents within the files must then
be inspected for mutilations, tears, stains or obliteration, and placed
in the proper orientation for filming. All paper clips and staples must
be removed, and folded or curled documents flattened; this is particularly
important when automatic feeders are to be used since folded or curled
documents can jam in the feeder. All camera operator or other targets
should be inserted in the files, and the camera operator should be notified
if any adhesives or pressure sensitive tape is present since the adhesive
can foul the feed mechanism or document beds of the cameras.
Record series or files are usually filmed in the order in which they
were originally created or maintained. However, filming provides an opportunity
to reorganize and rationalize file organization into a sequence that may
be more valuable to the user. Misplaced items should be placed in proper
sequence and extraneous materials purged. Missing items should be identified
and missing document targets inserted for filming.
While this process may sound simple and straightforward, it can be grueling
and devour unforeseen quantities of staff time if done in-house.
A number of non-record pages must be inserted among the records to be filmed. These targets may be informational for the persons using the film, or technical, relating the production and quality control of the film. The targets that must be included in filming are specified in 950 CMR 39.05(6) and the captioned ANSI standards, and include:
In recognition of the fact that all media are impermanent, microfilm is
no longer spoken of as archival. Rather, current terminology refers to
the length of time the film can be expected to survive under optimal conditions,
designated as the LE (life expectancy) rating. Currently, two types of
film base are in use for creating master microfilm negatives: cellulose-ester
and polyester. Cellulose-ester film has been in use since about 1908.
Experience and accelerated aging tests have shown it to degrade with exposure
to heat and humidity and in the course of use; based upon this rate of
degradation, it has been designated LE 100, or as having an expected usable
life of 100 years. Polyester film bases, introduced in about 1956, have
many advantages over cellulose-ester including greater strength, stiffness,
tear resistance, flexibility, and dimensional stability. Although actual
use experience has only been about 35 years, accelerated aging tests and
other investigations indicate that polyester base films will have a life
expectancy of 500 years and are rated LE 500. Since both types of film
are priced about the same, it is likely that cellulose-ester films will
tend to disappear from the market. Cellulose-ester films should only be
used when it is necessary to splice the microimages into previously created
rolls of the same stock. Records with a retention period of 15 years or
more must be filmed on polyester LE 500 stock.
Only non-flammable, safety film may be used.
Silver gelatin emulsion films must be used for the creation of first generation
master microfilms. These films consist of a film base coated with a light-sensitive
emulsion of silver halide crystals suspended in gelatin. When the source
document is filmed, the silver halide crystals exposed to the light (usually
blank) areas of the document are converted into free silver atoms, while
those exposed to the dark (text) areas are left unaltered. Thus, the light
from the source document passing through the camera lens and striking
the film surface forms a latent image. This latent image must then be
developed or processed to become stable and readable. During the development
or processing stage, discussed at more length below, chemicals are used
to convert the exposed halide crystals to metallic silver, thereby creating
black areas on the film, and to remove the remaining, unexposed silver
crystals, leaving these areas blank. The image thus formed is a negative,
or reversed image of the original document with text appearing white on
a black background.
During exposure, the light from the source document may penetrate the
emulsion layer and reflect back off the film base to form ghost images
known as halation. To prevent this, most film contains some type of antihalation
compound either integrated into the film as a layer between the emulsion
layer and the base or as a dye backing to the film.
There are three basic camera types used in making microfilm copies of
original documents. The choice of camera is dictated by the nature of
the source document, i.e., dimensions, paper weight, condition, or other
physical characteristics; the volume of documents; and the intended use
of the film product.
Rotary cameras, having the general size of an office photocopier, lend
themselves to the high speed filming of large volumes of documents. These
units are usually equipped with automatic feed mechanisms that feed documents
to the camera at a very high rate of speed. The high rate of throughput
is maintained by the camera mechanism that allows the lens to move in
tandem with the document, taking the picture while both are in motion.
The source documents filmed in this manner must be uniform in size and
weight to allow the automatic feeder to function properly. An ideal application
for this type of camera is cancelled checks.
Rotary cameras may also be provided with devices to automatically feed
unbursted computer printouts for filming.
Planetary cameras, by contrast, require the source document and the camera
to be stationary during the filming process. This provides a marginally
higher quality image than that provided by a rotary camera, along with
much greater latitude in the type and condition of the records that it
can film. Planetary cameras are the cameras of choice for archival microfilming.
The most common configuration for planetary cameras is a flat document
bed with dual light sources directed down on the document from above and
the camera suspended directly over the document. This arrangement allows
a wide variety of documents to be filmed, including full-size engineering
plans and bound volumes. Lighting may be adjusted to compensate for the
condition of the original document, and the camera can be shifted up and
down for a wide range of reduction ratios.
Another version of the planetary camera puts the lens and light source
below the document bed. This type camera closely resembles a photocopier
and documents are filmed in much the same manner as they would be copied:
face down on the document bed, or through an automatic feeder. This type
camera is not as versatile as the camera-above style.
The quality and versatility of the planetary camera must be weighed against
the fact that it is a slow and labor-intensive method of filming. In all
but the auto-feed mode, the source documents must be placed on the document
bed by hand and the shutter manually triggered. Even with auto-feed, the
documents must come to a full stop before the shutter is activated. The
throughput is limited to 800-1,000 documents an hour, equal to the capacity
of a rotary camera operating in manual-feed mode.
Step-and-repeat cameras are essentially planetary cameras specially designed
to create microfiche. A document is placed on the copy board, the shutter
is tripped and the document is exposed to the first position on the fiche;
the camera then steps to the next position on the film and the sequence
is repeated; hence, the name. Documents may also be automatically fed
in both the camera-over and camera-under configurations. Throughput is
slow, as with planetary cameras.
COM (computer output microfilm) recorders are not cameras as we typically
understand them but a combination computer peripheral and high-speed microfilmer
which converts binary, digital data into human-readable alphanumeric or
graphic information with no intermediate paper. The recorders may use
one of three technologies. In CRT photography, an image is displayed on
a CRT inside the recorder; the image is then photographed by a high-speed
microfilm camera. Laser beam recording uses directed lasers to record
information directly onto dry silver film in much the same way as in a
paper laser printer. Electron beam recorders, used mostly for graphics,
are a type of CRT recorder in which the electron beam is directed onto
the film rather than the display screen to create an image.
In roll film applications, images may appear in comic (horizontal) or
cine (vertical) mode. In comic mode, the images on the film follow one
after the other "like a comic strip" with the short axis of
the page and the text on it parallel to the long axis of the film. As
the film is scrolled through the reader, the images appear in a normal
readable pattern. In cine mode, the long axis of the documents is parallel
to the long axis of the film and when viewed in the reader the pages appear
to be on their sides. These images may be produced in simplex, duplex,
duo or duoduplex mode.
In simplex mode, a single image is created that fills the entire width
of the film. In duplex mode the front and back of the document appear
side by side across the width of one exposure. Duo records images along
one half of the usable width of the film, the exposures are made in one
direction then reversed and made in the opposite direction on the other
half of the film. Duoduplex uses mirrors to create side by side images
of the front and back of a document along one half of the film width,
when the roll is completed, the film is reversed and the process repeated.
Configurations of microfiche may be horizontal, vertical or serpentine
i.e., back and forth (or up and down).
One of the primary reasons for using microfilm is to reduce the size of
the original volume of records. The extent of this reduction is called
the reduction ratio. This is the number of times a given linear dimension
of the source document is reduced when photographed. Expressed as 24:1
or 24X, a reduction ratio of 24 means that both the horizontal and vertical
aspects of the source document have been reduced to 1/24th their original
size, yielding an image that is 1/576th the size of the original. For
archival microfilming, records should be reduced as little possible to
provide greatest resolution.
A wide variety of reduction ratios are available for use in microfilming,
but 24X is generally considered to be the standard when filming normal
documents. A reduction ratio of 32X is common for rotary cameras, however,
and the standard for COM is now 48X. Some applications, such as old manuscripts
or engineering drawings may dictate other reductions. In all cases the
primary consideration should be to create records which are of high quality
and compatible with the readers in use in the organization. The reduction
ratio must be able to ensure a resolution level of 8.0.
Resolution refers to the ability of the lens, optical system or emulsion to reproduce fine detail in the photographic reproduction of the original record. Since most microfilm is high-resolution film, the most likely areas for problems involving resolution to arise are in the optical system or camera lens. Lines should appear sharp and well defined. Using the Quality Index method described in Practice for Operational
Procedures/Inspection and Quality Control of First Generation, Silver-Gelatin
Microfilm of Documents (ANSI/AIIM MS-23), this means that a letter "e",
2mm high will resolve to the 5.0 test pattern. To ensure that this resolution
will be achieved, it is necessary that a series of test shots are taken
and read against the appropriate test charts.
Density is simply the amount of light that is stopped or allowed to pass
through the developed film. If density values are too low, the film will
appear faded or "washed out." On the other hand, too high density
will cause fine, light lines to fill and bold black lines to spread. The
density must be constantly monitored using a densitometer to ensure that
optimal density is maintained.
Exposing the film in the camera creates a latent image on the film. With
a latent image the chemical reactions that create a visible image have
been set in motion by exposing the sensitive film to light, but the image
is not yet visible and may still be altered or destroyed by additional
exposure. To transform the latent image into a visible one, the film must
now be processed or developed.
The development process essentially consists of immersing the exposed
film in an alkaline reagent that transforms the latent image to a visible
one by converting the exposed silver halide crystals to black metallic
silver. The process is then stopped in an acid bath after which the film
is fixed, that is, immersed in a "fixer" or "hypo"
solution to wash away the unexposed silver crystals to leave clear areas
on the film. The film is then washed in fresh water and dried. The images
created by this process have a negative polarity, that is, they show a
reversal of the light and dark areas of the original document. Some processors
can accommodate extra steps to reverse this polarization (reversal processing)
to create a positive image. Processing should be done within 24 to 48
hours of filming.
Processors are fully automated and self contained and range in size from tabletop to floor-standing. Processing generates large amounts of chemical waste including silver residues, which must be handled and disposed of with extreme care and in accordance with all applicable local, state and federal environmental and safety regulations.
Microfilming is a costly process and extreme care must be exercised throughout the entire program to ensure that records are properly prepared, filmed and processed. Following processing, post film inspection must be made to ensure that the film is of the highest possible quality. The following inspections must be made and reports filed:
Reports of the deficiencies found should be made and filed with the records
of the program.
If deficiencies are severe, it may be necessary to refilm the entire
roll. If only individual records are affected, these should be reshot
and spliced at the end of the roll along with the prescribed retake targets
and certificates. Only one retake section should be spliced to each roll.
Redox blemishes, or measles, are red spots that form on film due to the reaction of the silver with atmospheric pollutants. Left unchecked, the spots, which may start out as mere pinpoints, can grow in size and spread, eventually obliterating images or rendering them unreadable. Treatment of the film with gold, sulfides or selenide has been proven to provide a certain level of protection for film and to increase its longevity. Gold treatment is effective but quite expensive; selenium has been shown to be only partially effective. The best treatment for film to date is with sulfides. Kodak Brown Toner and IPI SilverLock are two products which involve bathing film in a polysulfide solution to convert the most of the silver in the processed microfilm to silver sulfide. Silver sulfide does not react with atmospheric pollutants and therefore has a greater longevity than untreated film. The treatment is inexpensive and relatively safe by both health and environmental standards. Use of this type of treatment is highly recommended. For further information, contact the Image Permanence Institute, Rochester Institute of Technology, 70 Lomb Memorial Drive, Rochester, New York, 14623-5604, 716-475-5199 or Eastman Kodak for more information.
The silver halide master film should never be used as a reference or working
film. It should be safely stored under the conditions described below
to serve as a security copy for the filmed records. Duplicate copies of
the master should be made for actual office and reference use. Duplicates
may be made from silver, diazo or vesicular films.
Silver gelatin duplicating film also called print film is also composed
of silver halide crystals suspended in an emulsion on a film base. The
master is duplicated to the print film by exposing it to light and the
latent image is developed in the same manner as the original master film.
The polarity of the duplicate will be reversed from that of the master.
The process is slow and costly, and usually limited to making a duplication
master from which other, tertiary copies can be made.
Diazo duplicating films are so named because they consist of an emulsion
of diazonium salts on the film base. When ultraviolet light is transmitted
through the master negative, the salts are dispersed in the areas of the
diazo film that correspond to the light areas of the master. The latent
image is then developed by exposure to ammonia fumes. Because of their
physical construction, diazo films are sturdier and can take more handling
and abuse than their silver emulsion counterparts, but they degrade much
faster and their image quality will become severely degraded after only
50 years. Diazo duplicates retain the polarity of the master negative.
Vesicular duplicating film consists of a light sensitive emulsion suspended in a thermoplastic resin on a polyester base. When ultraviolet light is transmitted through the master onto the vesicular film pressure pockets are formed creating the latent image. Rapid application of heat then develops the image by deforming the emulsion that hardens when the heat is removed. Image polarity is the reverse of the master negative.
Like all record media, microfilm is subject to degradation due to age,
handling and environmental conditions, and needs careful protection to
ensure its long-term survival. Diazo and vesicular duplicate films are
easily reproduced from the master negative or silver duplication master.
These films are also tough, scratch resistant and relatively tolerant
of suboptimal environmental conditions. These films are intended for office
use and can be stored under normal office conditions, avoiding extremes
of heat and cold and humidity. Care should be taken in handling, of course,
and the films, reader plates and drives should be kept clean and in good
operating condition.
The master negative should be safely stored in a secure, environmentally
controlled, fire and heat resistant area and should be used onlyin extreme
circumstances. Silver emulsion film is more fragile than the duplicate
films and, since the emulsion is an organic substance, is also susceptible
to greater environmental damage. Heat and humidity can weaken the emulsion
and also promote mold growth. Long-term retention of the master negative
film can only be ensured by storage under strictly controlled conditions.
The film must be stored in a vault constructed to the standards prescribed
in the National Fire Protection Association Publication NFPA 232, except
that the vault must be modified to allow for a heating/ventilation/air
conditioning installation to maintain the necessary environmental parameters.
The vaults must maintain a constant temperature of 70oF. or lower, and
relative humidity of 20-30% with daily fluctuations of not more than 5%.
The HVAC system must be fitted with air filters to prevent air-entrained
impurities from entering the vault. Because of the environmental requirements,
it is not feasible to store film in vaults primarily intended for the
storage of paper records. It may be necessary to seek a vendor who can
provide offsite vault facilities. The State Records Center, operated by
the Office of the Secretary of State, can provide such storage space,
free of charge. Small quantities of film may be stored in safes, UL class
150 rated for 4 hours (or equivalent).
All enclosures and storage containers for the master film must be chemically nonreactive and non-corroding. Materials used must also be chemically stable and resistant to giving off reactive fumes after heating to 150oF. for 4 hours. Great care must be taken that only photographically stable adhesives are used in containers and enclosures as provided in ANSI IT 9.2. If there is any question that proper humidity, ventilation or air purity will not be maintained, all film must be stored in sealed containers.
Periodic inspection of stored master negatives is essential. The procedures
for inspection of the film are set out in 950 CMR 39.07. Every 2 years,
a statistical sample of the total volume of microfilm must be inspected
for evidence of damage or deterioration. The inspection shall include:
rereading of resolution test target and remeasurement of films density;
inspection for residual processing chemicals, microbial growths, film
curl or discoloration, excessive brittleness, evidence of separation of
the emulsion from the base ("blocking or fused film"), adhesion
of the emulsion, base shrinkage and the presence of redox blemishes. Cans,
boxes, and reels of film should also be inspected for evidence of rust,
corrosion and other deterioration.
Problems that are noted in film or storage containers and housings are
often not isolated incidents, and if they are the result of conditions
subsequent to processing they can become contagious and spread throughout
the film collection. If samples of any lot of film rated as in fair condition,
additional samples must be inspected. All film of any lot rated as poor
must be inspected. All film rated as poor or bad shall be replaced.
Reports of the inspections shall be made to the Supervisor of Public Records.
In determining whether the program should be carried out in-house, there are a number of issues to be considered. An in-house operation has a number of advantages:
Conducting an in-house microfilm program is most effective in economies
of scale where there is sufficient work to fully employ both cameras and
operators. Where there is sufficient volume of material to be filmed,
an in-house program can result in significant cost savings and management
benefits.
An in-house program, however, involves a significant investment in equipment
and personnel. A simple desktop planetary camera will cost around $5,000,
and a low- to medium-volume rotary camera will run at least $10,000. If
the filming program is to be used for more than creation of security copies,
it must be flexible enough to accommodate a variety of film sizes, formats
and retrieval techniques and will require multiple cameras. Trained, skilled
personnel must operate the cameras; sloppiness or incompetence by the
camera operators can ruin an entire program, not only by spoiling a batch
of film, but also by destroying the faith of users in the quality and
usability of their output. A program depending on poorly trained, sporadically
employed personnel is doomed to failure.
A film program also requires that a considerable amount of space be dedicated
to the cameras and the document preparation area. Records must be processed
and filmed in secure, clean areas where their physical security and file
integrity can be assured.
Even in large-scale micrographics programs, the advisability of in-house
film processing must be carefully assessed. Processing involves chemicals
that may be governed by federal, state and local health, safety and environmental
regulations. Compliance with these regulations may require plumbing and
ventilation modifications to be made to the building, and involve a level
of compliance activity that would make in-house processing economically
unfeasible.
Careful cost analyses must be performed to determine whether an in-house program is realistic. There are three alternatives to such a program:
When selecting a microfilm vendor, it is important to consult with other
agencies which have gone through the process themselves and which have
experience in dealing with vendors. By tapping the experience of others,
you can anticipate the process and be aware of the virtues or failings
of the vendors who are likely to respond to your request.
At the request for proposal stage and throughout the entire project, it is essential to be able to communicate freely and clearly with the vendors. The vendors must be provided with sufficient information to submit an adequate response and they must be able to show that they are aware of all the factors that will influence their work on the program.
Since the vendor may require that valuable records be moved offsite, it
is highly recommended that he be required to post a bond to guarantee
their security. A bond should also be secured to ensure that the performance
of the vendor in terms of quality and delivery of the finished product
will be as promised.
To successfully formulate a response to an RFP and carry out a program,
the vendor must be provided with a variety of information:
The description of the records should also indicate if they are active or inactive, and the estimated retrieval frequency. The manner of retrieval and any particular reference patterns should also be noted to allow the proposal to be tailored to meet the needs of the records' users.
For their part, the vendors making proposals must provide certain information and proofs:
If the microfilm is to be integrated into an information management program,
the vendors must be able to show that they are thoroughly familiar with
other facets of such a program including paper document management, electronic
information management and optical data storage systems.
The vendor must also be able to show an operational flexibility that will ensure that the job will be completed on time in the event of unforeseen circumstances, even if this requires going to additional shifts.
Properly implemented, a well-thought-out micrographics program can provide a variety of benefits to government offices and be part of a powerful information management program. Improperly implemented, it can be a major waste of money. Preliminary study of the technology and the functions and dynamics of the office, and consultation with experts including vendors, professional associations such as AIIM and ARMA, and the Office of the Supervisor of Public Records are essential if the program is to succeed.
Brathal, Daniel A. and Langemo, Mark. Planning Conversions to Micrographic Systems. Prairie Village, KS: ARMA International, 1987.
Conway, Paul. "Relevance of Preservation in a Digital World." Preservation of Library and Archival Materials: A Manual. Andover, MA: Northeast Document Conservation Center, 1999. Also available at www.nedcc.org/tleaf55.htm. See also selected readings at www.nedcc.org/conbib.htm.
Dalton, Steve. "Microfilm and Microfiche." Preservation of Library and Archival Materials: A Manual. Andover, MA: Northeast Document Conservation Center, 1999. Also available at www.nedcc.org/tleaf51.htm.
Elkington, Nancy, editor. RLG Archives Microfilming Manual. Mountain View, CA: Research Library Group, 1994.
Fox, Lisa L., editor. Preservation Microfilming: A Guide for Librarians and Archivists. 2nd edition. Chicago, IL: American Library Association, 1995.
Kish, Joseph L. Micrographics: A User's Manual. New York, NY: Wiley, 1980.
Mims, Julian L. Using Microfilm. Albany, NY: National Association of Government Archives and Records Administrators, 1992.
"Resources for Facsimile Replacement of Out of Print and Brittle Books." Preservation of Library and Archival Materials: A Manual. Andover, MA: Northeast Document Conservation Center, 1999. Also available at www.nedcc.org/tleaf52.htm.
Saffady, William. Micrographic Systems. 3rd Edition. Silver Spring, MD: Association of Information and Image Management, 1990.
Saffady, William. Optical Disk vs Micrographics. Westport, CT: Mecklermedia, 1993.
Smith, Charles. Micrographics Handbook. Dedham, MA: Artech House, 1978.
Thomas, Bill. The Thomas Handbook of Quality Control in the Microfilm
Industry. Burnsville, MN: MicroD Interntional, 1990.
Standards for the production of microfilm are established by the American National Standards Institute (ANSI) and associated organizations and are available from:
American National Standards Institute
1430 Broadway
New York, NY 10018
Phone 212-642-4916
Fax 212-398-0023
Web www.ansi.org ANSI also distributes standards of the International
Standards Organization (ISO).
ANSI and ISO standards relating to microfilm and document imaging are
also available from the Association of Information and ImageManagement
(AIIM). AIIM is a professional organization dedicated to information and
image management and publishes its own journal, Inform. For more information
or a listing of ANSI or ISO standards and AIIM technical reports:
Association of Information and Image Management
1100 Wayne Avenue
Suite 1100
Silver Spring, MD 20910-5699
Phone 301-587-8202
Fax 301-587-2711
Web www.aiim.org
See www.aiim.org/industry/standards/97stdcat.htm for the AIIM catalog
of standards.
The Association of Records Managers and Administrators (ARMA) is another professional organization dedicated to efficient management of records. ARMA publishes a journal, Records Management Quarterly, and a number of publications for the guidance of persons in the records management field. Contact:
Association of Records Managers and Administrators
4200 Somerset
Suite 215
Prairie Village, KS 66208
Phone 800-422-2762 or 913-341-3808
Fax 913-341-3742
Web www.arma.org
The Society of American Archivists (SAA) is a professional organization that provides leadership, training and information for the identification, preservation and use of the nation’s historical records. SAA is an excellent source of educational material, including many of the resources listed in the bibliography. SAA also publishes the American Archivist and Archival Outlook. Contact:
Society of American Archivists
527 S. Wells, 5th Floor
Chicago, IL 60607
Phone 312-922-0140
Fax 312-347-1452
Web www.archivists.org
The Supervisor of Public Records is charged by Chapter 66 of the General Laws of Massachusetts with oversight of the public records of the Commonwealth, counties, cities and towns. Pursuant to this mandate, the Supervisor publishes the Records Management Manuals for state, municipal and county records. A series of policy statements, Supervisor's Bulletins, explicate policy on various issues and provide further guidance for record custodians. 950 CMR 39.00, Regulations on Using Microfilm, are a part of the Code of Massachusetts Regulations and govern the use of microfilm for retention of public records.
To obtain copies of these publications, visit the Records Management Unit Web site or contact:
Supervisor of Public Records
Massachusetts State Archives
Records Management Unit
220 Morrissey Blvd.
Boston, MA 02125
617-727-2816 Phone
617-288-8429 Fax
www.sec.state.ma.us/arc/arcrmu
RetentionHelp@sec.state.ma.us