Damage to Surface-Mounted (Diasec®) Photographs  

The nature of surface-mounted chromogenic color photography is to intimately join the photographic print with an acrylic glazing to create a single object inextricably fused together. Although visually this makes for an impressive presentation, as conservators we recognize that it presents a potential problem should any damage occur to the acrylic surface from either side. Any inadvertent damage in the form of a scratch, abrasion or crack comes very difficult to rectify satisfactorily using known conservation techniques. Extreme handling precautions are always recommended. Remember that with this mounting technique, the acrylic surface IS the surface of the artwork.

There are a number of physical damages that these pieces may be subjected to. Some types of scratches can be treated by careful application of an abrasive micro-alumina polish. The treatment is done under high magnification, with all possible care but the area around the deepest scratches will be altered and may be still visible, though reduced, even after treatment. Our goal is to soften the edges of the scratch so that it does not cast as deep a shadow and thus minimize the light-scattering effect. This kind of treatment can only be performed on a glossy acrylic surface as there is currently no reliable way for reproducing the texture of matte acrylic surfaces.

Acrylic is a very soft, gas permeable and an easily charged material. By wiping a dry cloth over the surface of this piece a static charge can be created that will attract more dust and other particulates. Although invisible at first to the naked eye, over the years these fine scratches can accumulate, aggregate and become visible as cloudy areas. Dry abrasion must be avoided by all measures when cleaning the surface of this work to avoid scratches. Similarly, the use of any solvent-based Plexiglas cleaners, even those designed for cleaning or polishing acrylic surfaces is to be avoided. Usually composed of proprietary ingredients that can be changed at the whim of a manufacturer, these commercial products, although effective in the short term, may possibly lead to future problems such as crazing and clouding of the acrylic.

Broken Glass  

Unfortunately, glass glazing is very fragile and can break easily causing damage to the photograph it was intended to protect. Photographs under broken glass are commonly gouged or lacerated in numerous areas causing flaps of loose emulsion and deep grooves, often with exposed fibers of the paper base. In addition to the gouges, there may be increased gloss or ferrotyping in several areas across the surface due to contact with the glazing. In such cases, repairs to the photographic surfaces are never completely invisible and they can always be seen upon examination and especially so in raking light. However, treatment can be successful in reducing the immediate visual impact of the considerable damage suffered and help stabilize the print against any further image loss. We strive to make the disruptions less prominent so that they are not the very first things that are noticed once the work is presented.

Mold  

Photographs exposed to a combination of poor storage and atmospheric conditions can suffer from mold damage. A mold damaged photograph will usually have numerous accretions of small mold colonies scattered across the surface that are readily visible, especially in raking light examination. These appear as small circular accretions (hyphae and spores) and in some instances may have already altered and discolored the underlying gelatin of the emulsion in which they were grown. It is possible to remove the mold bodies with mechanical action under magnification. This will greatly reduce their appearance, but where the surface has been physically compromised or stained, aesthetic reintegration will have variable results and will likely be apparent on close viewing especially in raking light. Physical reduction of the mold bodies and ensuring a stable, relatively dry environment are the best ways of discouraging reemergence of the mold.

Stuck to Glass  

Photographic surfaces can become stuck to their glazing if there is not adequate space in the frame to separate the photograph from its glazing. This problem is often caused by exposure to moisture or elevated humidity that allows the gelatin emulsion to swell and adhere to the glass. If the photograph is still in its damp state fast action is key and it should be removed by a conservator before being allowed to completely dry. If the damage has already occurred and the photograph is dry it may be possible to remove it through local humidification and physical manipulation. Some emulsion and image materials may remain affixed to the glass when glazing and photograph are separated. Should image material and binder remain adhered to the glazing, they can be removed and readhered in register to the print surface using an appropriate adhesive. Note that if this is the case, evidence of this damage will be apparent even after treatment. Please call or write to discuss this treatment option in more detail.

Laminate Removal

During post-processing treatment some photographs may receive a laminate layer, usually a thin, flexible plastic sheet adhered directly to the surface of the print. This often indicates the aesthetic choice of the artist. However, many of these plastic laminates are prone to deterioration that can cause their surface to become tacky and/or for the laminate to pull away from the photograph locally, usually around the edges of the print. This deterioration can be very distracting, completely changing the intended aesthetic of the work. In such cases it may be desirable to remove the laminate. This treatment procedure holds considerable risks that cannot be fully anticipated before treatment is underway. However, treatment also has the potential for a successful recuperation of the aesthetic qualities of the image. Previous projects of this nature show that plastic laminate materials may be removed mechanically along with residual adhesives from the print surface. However, these prior efforts may not accurately reflect the actual conditions in any one particular instance and both the adhesive and the laminate itself may have desiccated, hardened and/or cross-linked making removal problematic. The potential also exists for a separation of the binder layer from the primary paper support. This is a very involved process with many issues to consider and we strongly suggest that a client with this situation call or write to discuss this treatment option in much more detail.