Film handling
Handling film materials is a highly sensitive and technical process.
Film handling
Handling film materials is a highly sensitive and technical process.
Handling film materials in conservation is a highly sensitive and technical process that requires attention to detail, proper tools, and adherence to industry best practices.
The primary concern during handling is to prevent any damage to the film, whether through mechanical stress or contamination.
This section outlines key considerations and best practices in handling film to ensure the material is preserved and protected from degradation.
Staff training in handling procedures
Proper training is paramount for anyone handling films in a preservation setting.
The handling of films—whether they are in storage, being examined, or undergoing repair—requires a combination of skills and knowledge to ensure that no harm comes to the film during the process.
As films become more fragile over time, even the most routine handling actions must be performed carefully to prevent physical damage (Meyer et al., 2021).
Training should cover these key areas:
Recognising film deterioration
Understanding the signs of degradation, such as fading, brittleness, and colour shifts, is vital. Conservators should be trained to identify these changes early, allowing for the implementation of appropriate conservation measures before irreversible damage occurs (Jones et al., 2020).
Correct handling techniques
Proper handling techniques include wearing gloves to avoid direct contact with the film and using safe lifting and transport methods to avoid stressing the material (Lucas et al., 2019).
Understanding chemical hazards
Some films, particularly older acetate or nitrate films, may release harmful gases as they degrade. Staff should be educated on how to identify these symptoms and safely handle these materials (Hyun & Lee, 2020).
Emergency response
Staff should be familiar with protocols for responding to accidents, such as spills of solvents or accidental film damage.
Clean and organised work areas
Maintaining a clean and organised workspace is essential for preserving films. Dirty work areas introduce risks, including dust, dirt, and debris, which can cause scratches and contamination.
An unobstructed area is equally important to ensure smooth handling and prevent unnecessary interference with the process.
Key considerations for work areas:
Controlled environment
The temperature and humidity levels in the workspace should be controlled to avoid fluctuations that could affect the physical integrity of the film.
Fluctuating temperatures and humidity can cause films to expand and contract, leading to warping or embrittlement (Smith & Herring, 2017).
Clear paths
Maintaining a clutter-free environment ensures unhindered access to tools, film canisters, and other materials required during the handling process.
It also reduces the risk of accidental contact between the film and objects that could cause abrasions or contamination.
Regular cleaning routines
Work surfaces, tools, and equipment should be cleaned and sanitised regularly. Tools such as film winders and splicing devices must be free of residue and dust to prevent damage to the film during the repair or inspection process (Meyer et al., 2020).
Equipment maintenance and cleanliness
The maintenance and cleanliness of all equipment used in film handling are crucial.
Equipment used in film conservation, such as splicers, winders, and storage devices, must be in good working condition to prevent any mechanical damage to the film.
Additionally, improperly maintained tools can introduce dust, oil, or residue, which could lead to film contamination or degradation.
Key aspects of equipment maintenance:
Regular inspections
Regular checks and servicing of tools such as splicers and winders are essential. Any malfunction in this equipment could result in uneven winding or damage during the film repair process (Lucas et al., 2020).
Cleaning protocols
Tools should be cleaned thoroughly after each use, especially those that come into direct contact with the film. Using lint-free cloths and appropriate cleaning agents is necessary to avoid contamination.
Calibrating equipment
Film winders, in particular, require proper calibration to ensure they apply the correct tension to the film, neither too tight nor too loose, as improper tension can lead to deformation or stress on the film (Brouard et al., 2021).
Lighting for film handling
The quality and intensity of lighting used during film handling are critical for the practical examination and repair of film materials.
Proper lighting ensures that any defects or damage, such as scratches, tears, or splices, are visible and can be addressed before they cause further issues.
Lighting considerations include:
Lux levels
As per Australian Standard AS/NZS 1680.1:2006, the recommended lighting for precision tasks such as film handling is 600 lux. The lighting must be sufficient to highlight fine details on the film surface without being excessively bright, which can lead to glare or eye strain (Meyer et al., 2020).
Specular lighting
Specular lighting, which directs light in a manner that enhances the visibility of surface scratches and defects, is preferable for film inspection. This type of lighting allows for clear differentiation between the film surface and any flaws present (Hyun & Lee, 2020).
Bulb type
The shift from halogen to energy-efficient bulbs, such as LEDs, requires careful selection to ensure that the light output is suitable for detailed tasks like film inspection.
LEDs, though more expensive, provide a suitable alternative that offers specular light without the harsh glare associated with fluorescent bulbs (Lucas et al., 2020).
Quiet work environment
A quiet and undistracted environment enhances conservators’ ability to rely on \their tactile and auditory senses, which are critical for the early identification of problems.
Film damage is sometimes best detected by feel or sound before it is visible. For example, the sound of friction or the feeling of resistance when unwinding the film may indicate potential issues such as cinching or misalignment.
Key considerations for a quiet environment:
Minimising noise
Excessive noise can cause distractions and hinder conservators from detecting subtle issues. It is important to minimise background noise in the work area, using soundproofing techniques if necessary (Wells et al., 2020).
Use of tools
Tools such as winders and splicing equipment should operate quietly to maintain a peaceful working environment. Additionally, workers should be trained to identify any unusual sounds or vibrations from equipment, as these may signal a problem (Meyer et al., 2021).
Film cans and storage materials
The materials and methods used for storing films are just as important as the handling procedures. Films are susceptible to degradation from various environmental factors, including temperature, humidity, and exposure to light and air.
Proper storage containers—especially film cans—play a critical role in protecting the film from these harmful factors.
Film can enclosures
Film canisters serve as the primary storage method for films, designed to protect the film from physical damage and environmental pollutants.
Historically, film cans have been made from materials such as steel, aluminium, and various plastics.
While these materials offer a degree of protection, careful attention must be paid to ensure they are chemically stable and free from contaminants that could harm the film over time.
Key considerations for film can enclosures:
Materials
Plastics such as polyester, polyethene, and polypropylene are ideal for film canisters due to their chemical stability and inert properties.
Metals such as anodised aluminium and stainless steel are also suitable, provided they do not corrode (Meyer et al., 2021).
Avoiding harmful materials
Materials like PVC and nitrate plastics should be avoided, as they may release harmful chemicals over time, which can degrade the film (Lucas et al., 2020).
Issues with paper and adhesives
It is essential that no paper, especially acidic paper, be placed inside film canisters.
Paper materials can release acids and moisture, which accelerate the degradation of the film. Even high-quality archival paper must be used cautiously and stored separately from the film.
Key points regarding paper and adhesives:
Avoid paper in film cans
Paper can release harmful acids, moisture, and pollutants, which can damage the film over time. Adhesives, especially those used in rubber bands or labels, can also introduce reactive chemicals (Jones et al., 2020).
Alternative methods
Paper documentation should be catalogued and stored separately from the film, ensuring that the film remains in a controlled environment free from contaminants (Brouard et al., 2021).
Managing gases and corrosion
Films, particularly those made of acetate, release decomposition gases, such as acetic acid, as they deteriorate.
These gases can lead to further degradation if trapped inside an enclosure, which is why it is important to manage the airflow and ventilation within film cans properly.
Key considerations for managing decomposition gases:
Ventilation
Research by Newnham (2002) demonstrated that punching holes in the film may aid in releasing decomposition gases; however, these holes must be carefully positioned to ensure proper airflow. The film should also be elevated within the can to facilitate air movement.
Reusing film cans
While reusing old film cans is feasible, they must be thoroughly cleaned and tested for contamination to ensure safety. Certain materials, such as polystyrene, can adsorb harmful gases like acetic acid, making them unsuitable for reuse without proper cleaning (Newnham & Garvie, 2021).
Film cores and reels
One of the fundamental aspects of film handling is the use of film cores and reels, which allow films to be stored and transported without damaging the film base.
Proper selection of cores and reels is crucial to ensure that the film is stored securely and remains undamaged over time.
Film cores serve as a support structure for winding film, providing a convenient centre around which the film can be wound without risk of damage.
Film cores are typically manufactured to specific sizes based on film format, such as 35 mm, 16 mm, or 17.5 mm (for magnetic sound film).
The core size must be compatible with the film format to prevent damage to the film or create unnecessary tension during winding (Brouard et al., 2021).
Core size
The core diameter plays a significant role in the development of film curls during long-term storage.
Larger cores (75 mm or 100 mm) help reduce the effect of "cold flow" curling, which occurs when the film base polymer gradually takes on the shape of the core over time.
Smaller cores (50 mm) are not recommended due to the heightened risk of cold flow curling, especially with films made from cellulose triacetate, which is more prone to this phenomenon than polyester (Hyun & Lee, 2020).
Material compatibility
The material of the film core is equally important. Cores must be made from chemically inert materials to prevent any adverse reactions with the film.
Plastics used for film cores should be safe, as described in ISO 18911:2010, and should be free from harmful chemicals or contaminants, such as PVC, which can release harmful gases that degrade the film (Meyer et al., 2021).
Cardboard and wood cores should be avoided as they can introduce acids and moisture, which are detrimental to the film.
Film without a core or reel
Sometimes, films are received without cores or reels, particularly in cases of very old or improperly stored materials. In these cases, the film must be carefully handled and transferred to a suitable core or reel before further handling can occur.
Occasionally the core or part of the film will drop away while the film is being handled. This should be avoidable however it happens to many film archivists once at some point in their careers.
Dropped core
- Where just the core has dropped out it may be possible to gently replace the core by gently twisting it against the wrap of the film pack.
- Do not twist to vigorously otherwise the inner wraps of the film may cinch and scratch.
- If it is necessary cut small section of leader off and add a core, rewind the film and reattach the leader.
Where a large amount of film has fallen away:
- The reel will need to be carefully unwound from the outer portion and rewound onto the inner section.
- Flatbed winders are the best choice for this, however if these are not available vertical winders can be used in conjunction with a turntable.
If a splice is located near the section where the film has come loose:
- It may be possible to carefully undo the splice and unwind the outer portion of the film, rather than attempting to rewind it back onto the reel.
- If this method is attempted, it is essential to ensure the splice is securely remade and that no frames are lost in the process.
- If there is any uncertainty about the splice's integrity or the possibility of damaging the film, it is advisable to discontinue this approach.
- This careful handling prevents the film from shifting or cinching during subsequent examination or repair (Smith et al., 2020).
Winding the film
Use winding plates to support the film from both sides.
This ensures the film does not become misaligned during handling and maintains a secure, even wind on the core (Lucas et al., 2020).
Emulsion in or out?
A common question in film preservation is whether films should be wound with the emulsion side in or out.
According to the SMPTE Recommended Practice RP 39-1993—Specifications for Maintaining an Emulsion-In Orientation for Theatrical Release Prints—films that are wound with the emulsion side in from the time of processing experience less focus drift during projection.
This practice, primarily based on the characteristics of acetate-based films, remains widely followed. Kodak recommends adherence to RP 39 for ESTAR (polyester)-based projection films as well. However, a general practice among projectionists suggests treating polyester films differently by winding them emulsion out.
RP 39 is primarily applied to 35 mm and 70 mm films, where the emulsion faces towards the lamp and the base towards the lens (as per SMPTE Standard 194-1991). For other gauges, such as 16 mm, the emulsion can face either direction, depending on the post-production process (e.g., A-type or B-type).
Thus, there is no universally recommended emulsion orientation for 16 mm films.
Some archives implement a policy of reversing the winding direction for newly acquired films, changing the emulsion orientation from the way it arrived (i.e., from emulsion to emulsion or vice versa).
This practice is designed to reduce the effects of curl induced by polymer cold flow, making the film easier to handle during future examinations. Polyester films are particularly prone to a persistent curl known as the core set, which develops when films are wound in one direction for long periods. Reversing the emulsion direction and using a larger core size (e.g., a 75 mm core instead of a 50 mm core) can help minimise the effects of the core set.
In terms of chemical decomposition, there is no significant difference between winding a film emulsion in or out. The critical factor is the tension applied during winding. However, it is important to ensure that all colour separation masters are wound in the same manner, as well as to use consistent core sizes for all reels in the set. This ensures that any shrinkage is uniform across all reels, maintaining the integrity of the film set as a whole.
Winders and winding practices
Film winders are either horizontal, with a disc like a turntable, or vertical, with a disc like a vehicle wheel.
Setting up winders
The proper alignment of vertical winders is essential to ensure the film is wound evenly and with precision. The winders must be positioned so that the plates are perfectly aligned, preventing any irregularities in the winding process.
When using winders with cores and plates, it is recommended to angle the right-hand winder by approximately 1-2 degrees clockwise. While the conventional method is to wind film from left to right, if the process requires winding from right to left, the left-hand winder should be adjusted similarly in the opposite direction.
Canting the winder creates a gentle edge against which the film can wind, ensuring an even and smooth wind. This also prevents leafing—where layers of film sit above the pack, becoming susceptible to damage. However, excessive angling can cause the film to twist against the plate, leading to undue pressure on the film and potentially resulting in damage.
Aligning film winders
Maintaining the precise alignment of winders is particularly important when they are used for projection reels. Correct alignment reduces the risk of edge damage caused by sharp protrusions, distortions, or flaws in the reel flange. Running the film along a damaged or misaligned reel flange can cause edge damage, which may negatively impact the film's preservation.
Winders should be carefully adjusted to suit the specific film being handled. This ensures the film is wound at an appropriate tension, thus preserving its structural integrity over time (Bigourdan & Reilly, 2019).
Winder plates and spring locks
Plates and spring locks are essential for securing the film during the winding process. These plates should match the film gauge and the length of the film. If the plates are incorrectly sized, the film can spill over the edges, leading to tangling and potential damage (Brouard et al., 2020).
In the case of shrunken films, modifying the plates to fit the film better can ensure that it is wound tightly and evenly, thereby preventing further complications during the winding process (Meyer et al., 2021).
Tension control
Tension control during the winding process is crucial for maintaining the film's integrity. Excessive tension can cause physical damage to the film, while insufficient tension may result in the centre of the film pack dropping out.
Maintaining a consistent, moderate tension throughout the winding process is vital. For preservation purposes, a 'low tension' wind is recommended, as it minimises physical stress on the film (Newnham et al., 2021).
Handling and securing wound film
Once the film is adequately wound onto a core or reel, it must be securely fastened to prevent damage during storage or transport.
Securing wound film
The end of the film should be fastened with a small strip of adhesive tape that does not come into direct contact with the film surface. This ensures that the film does not unravel while still allowing for easy removal and rewinding when necessary.
Adhesive tape
It is essential to use adhesive tape that is safe for photographic materials and has been tested using the Photographic Activity Test (PAT).
Film splicing tape is often the best option, as it is specifically designed for use with films and certified for archival use (Brouard et al., 2021).