Preventive Conservation
Photographs are physical objects. They are subject to degradation and damage from the environment and improper handling. Images can fade, colours can shift, surfaces can crack, and paper can tear or become contaminated with insects or moulds. Repairing damage already done is called restoration. Preventing or minimizing damage is called preventive conservation.
Preventive conservation can be practised when handling, displaying, and storing photographs.
General Characteristics
Handling
Display
Storage
General Characteristics
Some types of photographs are inherently more long-lived. Black-and-white prints tend to last longer than colour prints. While the silver in black-and-white photographs can fade and yellow under unfavourable conditions, the process can be slowed with proper housing and storage. The organic dyes of colour photographs go on fading, even when they are protected.
Some black-and-white prints are poorly processed when made. Residual chemicals in the emulsion (image layer) and paper support can cause deterioration. Fingerprints left on a wet print can show up years later.
Return to the topHandling
The most common problems with photographs are caused by handling. Creases, scratches, cracks, tears, broken cardboard supports, and abrasions can be avoided by working on a clean, flat surface, protecting the photograph in a good quality paper or plastic sleeve, wearing gloves, and securing long hair and dangling jewellery or clothing.
Display
Light causes photographic images to fade and discolour significantly. Light exposure should be limited, especially for colour prints and 19th-century photographs.
Good-quality cardboard mats and frames fitted with ultraviolet filtering Plexiglas will help protect prints on display from physical and chemical damage. Avoid hanging prints in direct sunlight.
Condensation can result when the gelatin emulsion of a modern photographic print is placed directly in contact with the glass in a picture frame. Over time, this may cause the print to adhere to the glass, making it impossible to remove the print without damaging the image. Use a cardboard window mat or spacer to keep the print and glass separate.
Another option is to make display copies of images for permanent display. Most camera and film processing shops have the equipment to scan original prints and produce copy prints.
Return to the topStorage
The air quality surrounding photographs is critical. Air pollutants, heat, and humidity can accelerate damaging chemical reactions. Extremes - such as a hot attic or damp basement - should be avoided. Interior rooms or closets without exterior walls usually have the most moderate climate. Avoid places that are susceptible to drips or floods. If a photograph gets wet, dry it as soon as possible in freely circulating air.
Many species of insects and mould thrive on the paper supports and gelatin coatings of photographs. Avoid storing photographs in parts of the house where insects are common.
Albums or individual housings made of good quality paper or plastic provide another level of protection for stored photographs. The paper works as a humidity buffer, moderating the extremes or sudden changes in humidity to which the photograph would otherwise be exposed.
Precious colour negatives can be sealed in air-tight food-storage bags and placed in a freezer. Double bags with good-quality paper or cardboard inside are best.
Some storage materials should never be used. Paper clips, staples, rubber bands, "magnetic" album pages, self-adhesive tapes, poor quality adhesives (like animal hide glue), and acidic, poor quality paper will all cause damage.
Return to the top1900
Date: c. 1900
Medium: Gelatin silver print on a cardboard mount
Observations: As with many old photographs, the condition of this print and its mount is excellent. The brown and pink tones of the image are the original colours. The paper covering the cardboard mount may fade if it is exposed to too much light.
Date: 1902
Medium: Gelatin silver print on a cardboard mount
Observations: This print has sustained some physical damages - small tears and losses around the edges and abrasions and marks on the surface. The cardboard mount has become brittle and will be further damaged if it is not put into good protective housing. A plastic sleeve would work since you want to be able to read all the inscriptions on the back without removing the print from its housing.
1910
Date: c. 1910
Medium: Gelatin silver print
Observations: This kind of damage often occurs when someone tries to remove a print pasted into an album. Luckily, in this case there happens to be a duplicate intact print. Don't ever use adhesives directly on photographic prints.
Date: c. 1910
Medium: Gelatin silver print on a cardboard mount
Observations: This beautiful portrait comes with the mount and folder supplied by the commercial studio that made the portrait. These mounts are important to preserve because they add to the meaning and the interest of the object. Sometimes, though, the mount cardboard is more subject to damage and deterioration than the photograph mounted on it.
1920
Date: c. 1920
Medium: Gelatin silver print in a plastic frame
Observations: The period frame that houses this portrait makes this object even more meaningful and interesting. Even though it is broken, it should be saved and protected from further damage.
Date: c. 1920
Medium: Gelatin silver print (postcard format)
Observations: Commercial photographers in this era gave you the choice of having your portrait printed as a postcard. This one was never sent. It shows minor wear around the edges and a bit of paper has become stuck to its surface. Don't try to remove such accretions or you may cause some serious damage.
1930
Date: 1934
Medium: Gelatin silver print
Observations: This little print was probably an i.d. photograph used on a driver's licence or other legal document. The hole, the trimmed corners, the red-ink stamp and the inscription on the back are all part of its historical context, showing how this photograph was used.
Date: 1934
Medium: Gelatin silver print
Observations: The commercial photographer in Warsaw who made this portrait put his studio blindstamp in the bottom left corner. You have to look carefully to see it. Often you can find out interesting information about the meaning and origin of an old photograph by carefully examining all the marks that have been made on it.
1940
Date: c. 1940
Medium: Gelatin silver print
Observations: Sometimes what is written on a photograph changes your whole perception of the person or thing depicted. This portrait becomes a lot more interesting when you start to think about it along with the question jotted down on the back.
Date: c. 1940
Medium: Gelatin silver print
Observations: This print shows a kind of metallic surface sheen in the darkest parts of the image shadows. This "silver mirroring" or "silvering-out" is caused by a kind of seepage of the silver image particles from the gelatin film out towards the surface. It is driven by exposure to high humidity and polluted air. Prevent further silvering-out by housing this print in a plastic sleeve with a cardboard or paper insert.
Date: c. 1940
Medium: Gelatin silver print
Observations: With the exception of a slightly dog-eared corner, this 60-year-old photograph is in excellent condition. You can keep it that way by proper housing and storage and careful handling.
1950
Date: c. 1950
Medium: Gelatin silver print
Observations: This print has a small number written in pencil in the sky area of the image, as well as an extensive blue ink inscription on the back. Never try to erase or wipe away what is written on the image side of a photograph: the rubbing action can damage the photographic emulsion.
Date: c. 1950
Medium: Gelatin silver print
Observations: You can often find details about how photographs were made by careful observation. Notice the white circles and lines at the corners of this print. They are the shadows of the pins that were used to fasten the printing paper to a board in the darkroom while the negative image was projected onto it during the printing process. This probably means that this print was produced in someone's home darkroom rather than being produced by a commercial printer.
1960
Date: 1962
Medium: Chromogenic print
Observations: This print came with its own display folder and its condition indicates that it probably was kept on display, exposed to light, for a substantial period of time. Chromogenic colour prints form their full colour images by depositing varying amounts of three colour dyes in the emulsion layers. The three dyes are yellow, magenta and cyan. In many chromogenic papers, the yellow is the one dye of the three that fades fastest in the light, causing a shift towards its complementary colour, blue. (Note that we can readily date this image by finding the year on the car's licence plate.)
Date: 1966
Medium: Gelatin silver print
Observations: This black-and-white print is in perfect condition, something that cannot be said of most of the colour prints made during this era. The silver particles that make up the image are largely unaffected by light and are well protected against oxidation (a kind of silver "tarnishing") by the gelatin emulsion that surrounds the particles. If this print is kept in dry, clean surroundings, it will last for a very long time.
Date: c. 1960
Medium: Instant silver print (Polaroid)
Observations: With this type of Polaroid print, you peeled apart the sandwich of paper and chemical layers that came out of the camera, revealing the developed print. After this you were meant to coat the print with a protective solution. A small sponge applicator filled with this solution came with every Polaroid material cartridge. If this wasn't done, or wasn't done completely, it left the silver image vulnerable to oxidation and fading, as is the case with this image where the top half of the image has faded to a pale brown.
Date: c. 1960
Medium: Gelatin silver print
Observations: Here's another print that has probably been exposed to a lot of light over the years, judging by its colour shift towards the blue (representing yellow dye loss). Staples should never be used on prints or their mounts; they will eventually cause rust stains on the paper.
Date: c. 1960
Medium: Gelatin silver print (Fotomat print)
Observations: Photo booths - like those featured in the recent French movie, Amelie - have almost all disappeared from our cities, but they used to be a common sight in bus and train stations and shopping malls. You could get a series of four different portrait shots taken and processed automatically by the machine while you waited. Digital descendants of the photo booth are used commercially today.
1970
Date: c. 1970
Medium: Gelatin silver print
Observations: The orange stain that has spread irregularly across this print was a common problem with early versions of the plastic coated papers - called RC paper - that photographic manufacturers began to use in the 1960s and 70s.
Date: c. 1970
Medium: Chromogenic print
Observations: The colours of this image have faded and the paper has yellowed, shifting all of the original colour values.
Date: c. 1970
Medium: Chromogenic print
Observations: Chromogenic colour prints form their full colour images by depositing varying amounts of three colour dyes in the emulsion layers. The three dyes are yellow, magenta and cyan. Even prints that are protected from light exposure by being kept in an album or a box will often show a colour shift toward the red. This is because the cyan dye tends to fade away slowly, even in the dark, shifting the tone of the print towards red, the complementary colour to cyan.
Date: c. 1970
Medium: Instant silver print (Polaroid Type 55 P/N)
Observations: All types of Polaroid prints are somewhat vulnerable to deterioration. Here, there is some orange coloured staining near the top right and the print seems to be losing contrast overall. These prints need to be protected from light, moisture and polluted air.
1980
Date: c. 1980
Medium: Chromogenic print
Observations: This print appears to be in near perfect condition. Keep it that way by keeping it in a photo album and storing the album away from sources of humidity and heat.
Date: c. 1980
Medium: Chromogenic print
Observations: You might think that the cool blue tones in this image mean that it is shifting towards the blue. But if you check the skin tones, you can see that the print is unfaded. It's just a blue-green toned image because of the lighting conditions present when it was made.
Date: c. 1980
Medium: Chromogenic prints, mounted on a self-adhesive ("magnetic") album page
Observations: These prints are in big trouble because they have been put into an album that has plastic page covers coated with stripes of adhesive. The adhesive will deposit on the back and the front of the prints where it will cause deterioration of the images and will attract dust and dirt that will be impossible to remove. The cardboard and plastic of the album page is already deteriorating - as can be seen by the developing orange stains.
1990
Date: c. 1990
Medium: Chromogenic print
Observations: Recent prints can be preserved by keeping handling down to a minimum, housing them in a plastic storage/viewing page, and storing the page in a clean, cool and dry place.
Date: c. 1990
Medium: Chromogenic print
Observations: If you want to frame and display a print, have a copy made for display and preserve the original in dark storage.
2000
Date: c 2000
Medium: Chromogenic print
Observations: It's a good idea to write some information on the back of your recent prints. The subjects name and the date of the picture will make the image a lot more meaningful in the future. Use a non-fading fine-tip felt pen - these can be purchased at artist's supply stores.
Date: c 2000
Medium: Chromogenic print
Observations: If the image originates as a digital file, give it a comprehensible file name and keep it in a central image sector on your computer hard drive; the image file should be in an uncompressed or lossless format.
