Guides
How to sequence a family photograph project from triage to storage
A working sequence for family photographs: identify the processes, set the conditions, copy what is fragile, then house the originals and leave them alone.
What to take away
- Photographs want cooler and drier conditions than paper documents, and film negatives want drier still.
- Copy first, then store. An original that has been duplicated can be put somewhere inconvenient and safe.
- Color prints fade in a specific order. Cyan goes first, which is why old snapshots turn red.
- Handling does most of the visible damage. Fingerprints on an emulsion are permanent stains, not smudges.
Set the conditions before anything else
The Canadian Conservation Institute's guidance on caring for photographic materials gives a humidity range with reasons attached, better than a bare number. Higher humidity speeds deterioration: many chemical processes need water.
Humidity range for photographs
- Below 20-30%brittle, cracks
- 20-65%safe zone
- Above 65%mold, softens
Lower humidity slows reactions such as acid hydrolysis. But too dry is also wrong: below roughly 20 to 30 percent, desiccation makes gelatin brittle enough to crack.
The upper limit is the one to act on. It gives below 65 percent relative humidity as the safe zone for preventing mold and gelatin softening.
Above it, gelatin softens and sticks to glass or whatever it touches; closely packed negatives and prints can adhere into a solid block; and gelatin becomes a rich nutrient for mold.
Rapid swings cause their own damage. Because the layers of a photograph expand and contract at different rates, quick humidity shifts produce curling, cupping and cracking, worst of all in framed work held flat by a mat and glazing. Pick the most stable room you have, not the one with the best average.
Identify what you are holding
Photographs are not one material. A daguerreotype, a glass plate, an acetate negative, a fiber-base print and a 1990s color snapshot fail in different ways and want different housing. Sort by physical type before you sort by family member.
Photograph types and their needs
Type
- Cased images
- Never freeze
- Glass plates
- Store on edge
- Film and slides
- Check vinegar smell
- Fiber-base prints
- Most durable
- Color prints
- At risk from light
Handling note
- Cased images
- Glass plates
- Film and slides
- Fiber-base prints
- Color prints
- Cased images on glass or metaldaguerreotypes, ambrotypes, tintypes. Never freeze these.
- Glass plate negatives. Heavy, brittle, stored on edge in divided boxes.
- Film negatives and slides. Check for a vinegar smell, which means the acetate base is decaying.
- Fiber-base black and white prints. The most durable thing in most collections.
- Color prints and slides. The most at risk from light and heat.
Copy before you store
Mary Lynn Ritzenthaler, a National Archives conservator, writes on preserving family photos. Color needs priority: cyan, magenta and yellow dyes fade, shift or discolor.
Copying order
- Color slides and prints first
- Then anything showing damage
- Then everything else
Cyan fades faster than the others, so old images often look red. Photos not thoroughly washed during processing can carry yellow or brown stains. Digital images avoid fading but are lost entirely when a drive fails.
That sets the copying order. Color slides and prints first, then anything showing damage, then everything else. Once an item has a good copy, the original stops needing to be accessible, which frees you to store it somewhere cold and awkward.
Housing, and the order of work
Stage / Task
- 1
- Sort by physical type, not by subject
- 2
- Measure the room; pick the driest stable space
- 3
- Copy color and damaged items
- 4
- Sleeve and box by type and size
- 5
- Label the outside; write nothing on originals
- 6
- Set a reminder to check in six months
Handling rules run through all six stages. Do not touch print surfaces, because fingerprints cause permanent stains on every type of photograph. Support prints and mounts with two hands, or lift them in a folder or on a piece of mat board. Keep hands clean and free of lotion.
Our list of what to buy first covers enclosures for each of these types, and the notes on running a collection in a small flat cover what to do when the driest stable space is a cupboard.
Common questions
Should I scan everything?
Are photo albums safe to leave assembled?
Do negatives matter if I have the prints?
What about a vinegar smell in a negative box?
In this guide
- Risk in a photo archive: it follows the material, not the subjectRisk in a photograph collection follows the material, not the subject. How to spot nitrate and acetate film, cased images and color, and what each one needs.
- What to buy first for a photo archive, paper or plastic, buffered or neutralWhat to buy first for a photograph collection: paper or plastic, buffered or neutral, sleeve or envelope, how to choose photograph enclosures.
- Photo Archives Cost: Factors, Not Price QuotesPhoto archives cost depends on size, copying method, and storage target; learn how these choices shape a project without a flat price list.
- Cupboard versus closet for a small photo archive, ranked by riskRunning a photograph archive without a spare room: choosing the least bad cupboard, monitoring it properly, and using an upright freezer as cold storage.
- Learning photograph care, and judging a lab's workWhere to learn photograph preservation without naming studios, plus the inspection routine that tells you whether a copying job came back good enough.
