Preserving Historical Photos and Documents

Old photographs and papers rarely fail all at once. They fade a little every year in a sunny room, curl and crack in an attic that swings from freezing to 120 degrees, grow mold in a damp basement, and stain where a rubber band or a strip of tape touched them decades ago. Almost all of that damage is preventable with a few inexpensive decisions: where you keep the box, what the sleeves are made of, and whether a good scan exists somewhere other than your house. This guide gives you the specific targets that archivists use (temperature, humidity, enclosure standards, scanning resolution, backup rules) and shows you how to apply them at home without a conservator's budget.

1. Pick the Right Spot in the House

The Library of Congress recommends storing photographs in an environment that is relatively dry (30–50% relative humidity), cool (70°F or below), and stable, and it calls relative humidity the single most important factor for most photographic prints. High humidity softens gelatin emulsions, encourages mold, and makes prints stick to each other and to plastic sleeves; very low humidity makes old prints and paper brittle. Rapid swings are worse than a steady condition slightly outside the ideal range. For color prints, color slides, and film negatives, temperature matters most, because the dyes and film bases decay chemically, and the Library recommends cold storage (40°F or below) for them when possible.

In practice, that rules out the three places families usually use: the attic (heat), the basement (humidity and flood risk), and the garage (both). An interior closet or under-bed space on the main floor of a heated and air-conditioned house is usually the best spot you have. Keep boxes off the floor, away from exterior walls, radiators, and bathrooms, and out of direct sunlight. An inexpensive digital hygrometer (a temperature and humidity monitor) tells you whether the spot actually stays in range through summer and winter.

2. Use Enclosures That Pass the Photographic Activity Test

Many papers, cardboards, and plastics give off acids, sulfur compounds, or plasticizers that stain and fade photographs. The Library of Congress recommends storage materials that meet ISO 18902 and that pass the Photographic Activity Test (PAT), a standardized test (ISO 18916) that checks whether an enclosure material reacts with photographs. Reputable archival suppliers state "passes the PAT" in their product descriptions; if a sleeve or box does not say so, assume it has not been tested. "Acid-free" alone is not enough, since a paper can be acid-free when sold and still contain lignin that becomes acidic over time, so look for "acid-free, lignin-free" paper and board.

• Plastic sleeves: uncoated polyester (sold under names such as Mylar D or Melinex), polypropylene, and polyethylene are the safe plastics. Avoid PVC (vinyl), the soft, shiny plastic with a strong smell used in cheap photo pages and binder sleeves.
• Paper enclosures: PAT-passed paper envelopes and folders are better for photographs that are flaking, cracked, or tacky, and for any photo kept somewhere humidity may rise above about 70%, because emulsions can stick to plastic in damp conditions.
• Boxes: store sleeved photos upright or flat in lidded, acid-free, lignin-free boxes sized to the items, so nothing slumps or slides. Fill gaps with acid-free board rather than leaving a half-empty box.
• Separate negatives from prints. The Library of Congress notes that some aging negatives give off gases that harm nearby photographs, and it advises against plastic enclosures for nitrate or acetate negatives; use paper negative sleeves instead.

3. Rescue Photos from Magnetic Albums, Frames, and Shoeboxes

The "magnetic" or self-adhesive albums sold from the 1970s onward, with a sticky cardboard page under a clear plastic sheet, are among the most damaging things a family photo can be stored in. The adhesive yellows and becomes acidic, and the cover sheet is often PVC. If photos lift off easily, remove them and sleeve them. If they are stuck, do not pry: slide a thin metal spatula or unwaxed dental floss behind a corner; if that does not work, scan or photograph the whole page in place and leave stubborn prints for a conservator. Before you dismantle an album, photograph each page, since the arrangement and any captions are historical information in themselves.

Also take out rubber bands, paper clips, staples, pins, and sticky notes; the Library of Congress lists all of them, along with self-adhesive tape and glue, as things never to use on photographs. Framed photos that have hung in sunlight for years should be checked for fading and for prints stuck to the glass; if a photo is stuck to glass, leave it in the frame and take it to a conservator. For display, hang a scan or a print made from a scan and keep the original in its box.

4. Handle and Label Without Leaving a Mark

Handle photographs with clean, dry hands or clean nitrile gloves, by their edges or by their sleeve, and never touch the image area; fingerprints etch into emulsions over time. Gloves are most useful for metal, glass, and plastic objects such as tintypes, glass plates, and film negatives. Remove loose dust with a soft brush or a hand blower bulb, not canned air or a damp cloth.

Identifications are the most valuable thing you can add to a collection, but put them in the right place. The Library of Congress advises avoiding marks on photographs where possible and, if necessary, writing on the back near the edge with a soft graphite pencil. Never use ballpoint pens, which emboss through to the image, or felt-tip markers, whose ink can bleed and transfer. Better still, write names, places, and dates on the sleeve or on an acid-free paper slip filed with the photo. Our guide to dating old photographs helps you estimate dates for the ones nobody can identify.

5. Know Which Items Need Special Care

• Cased images (daguerreotypes and ambrotypes) should stay in their original cases. Do not open the package or clean the plate; a daguerreotype surface can be wiped away by a single touch.
• Old film negatives made before the early 1950s may be cellulose nitrate, which is a fire hazard as it decays. Look along the edge: film marked "SAFETY" is not nitrate. Unmarked old negatives should be stored apart from other materials, scanned soon, and shown to a conservator or archive if they are sticky, brown, or smell acrid. Later acetate "safety" film can develop vinegar syndrome, a vinegar smell accompanied by curling and shrinking; isolate those negatives and digitize them first.
• Color prints and slides from the 1950s through the 1980s often show heavy dye fading, typically turning red or orange. Fading cannot be reversed physically, but a scan can restore much of the color digitally, so these belong near the top of your scanning list.
• Peel-apart and integral instant photos (Polaroids) should not be cut, trimmed, or pressed, since the chemical layers can leak.
• Documents: unfold letters and certificates and store them flat in acid-free folders; keep newspaper clippings in separate folders (or copy them onto acid-free paper), since newsprint becomes acidic and stains whatever it touches. Do not laminate anything; lamination is irreversible.

6. Scan at the Right Resolution and Keep Master Files

A good scan protects the image even if the original is lost in a fire or flood, and it lets you share copies without handling the original. The Library of Congress's personal digital archiving guide suggests scanning documents and ordinary 4×6 and 5×7 photos at 300 dpi (ppi), using 400 or 600 dpi if you may want to enlarge them to 8×10 or larger, and scanning slides, which are much smaller, at around 1,900 dpi. A sensible home standard that covers most cases:

• Documents and letters: 300–400 ppi, in color or grayscale (not black-and-white "bitonal" mode, which drops faint ink and pencil).
• Prints: 600 ppi for snapshots and small cartes de visite or tintypes, 300–400 ppi for 8×10 and larger prints.
• Slides and 35mm negatives: at least 1,900 ppi, using a scanner with a transparency lid or a dedicated film scanner, because a flatbed's ordinary lid cannot light film from behind.
• File format: keep an uncompressed or losslessly compressed TIFF as your master if you have the storage space, and make JPEG copies for sharing; if you save only JPEGs, use the highest quality setting and never re-save the master after editing.

Clean the scanner glass before each session with a microfiber cloth, never force a curled or brittle item flat, and scan the backs of photos that have writing or studio imprints. Phone apps such as Google PhotoScan reduce glare and correct perspective and are fine for quick copies of a large collection, but a flatbed scan is sharper and is the better master copy of anything important. Keep the unedited scan as the master, and make retouched or color-corrected versions as separate, clearly named files.

7. Name, Describe, and Back Up Your Files

A folder of files named IMG_0043.jpg loses most of its value the day the person who scanned it is gone. Use a consistent file name that sorts by date, such as 1952-07-04_Kessler-family_porch_001.tif, putting the year first so files sort chronologically and using hyphens or underscores instead of spaces and special characters. Record who, what, where, and when for each image, either in a simple spreadsheet keyed to the file names or in the image's embedded metadata (the "description" or "caption" field that most photo programs can edit). Note what is known versus guessed.

For backup, the widely used 3-2-1 rule is a good target: three copies, on at least two kinds of storage, with one copy off-site. A typical home setup is the working files on your computer, a second copy on an external hard drive, and a third copy in a cloud service or on a drive kept at a relative's house. The Library of Congress also recommends moving your files to current storage media about every five to seven years, since drives fail and formats age; check that files still open whenever you copy them.

8. Share Copies with Family and Local Archives

Spreading copies is itself a form of preservation. Send scans to relatives, upload identified photos to a family tree site (FamilySearch's Memories feature is free), and offer copies of street scenes, storefronts, schools, and events to your local historical society or public library, which may be the only place a picture of a vanished building survives. Many societies will scan items and return the originals, or accept originals under a written deed of gift; our guide to finding your local historical society explains how to approach them, and you can find the right one in our directory of historical societies by state.

Before you post photos publicly, think about copyright and privacy. In the United States, works published before 1931 are in the public domain as of 2026, but unpublished photographs follow different rules: generally the photographer's life plus 70 years, or 120 years from creation when the photographer is unknown. A family snapshot taken by your grandfather is usually yours to share as his heir, while a studio portrait or a newspaper photo may still belong to someone else. People in recent photos may also prefer not to be identified online.

9. When to Call a Conservator

Home care is about prevention and housing. Repairs are a different matter: torn, flaking, moldy, water-damaged, or stuck-together photographs, cased images, and brittle documents should go to a professional photograph or paper conservator, because well-meant home fixes (tape, glue, household cleaners) often cause permanent damage. The American Institute for Conservation's Find a Conservator directory lists professionals by specialty and region, and the Northeast Document Conservation Center publishes free preservation leaflets on photographs, paper, scrapbooks, and emergency salvage. If photos get wet in a flood, the common first-aid advice is to keep them wet in clean water and get them to a conservator, or air-dry them face up as soon as possible; do not let wet prints dry stacked together.

Tips for Preserving a Family Collection

• Triage first. Scan and rehouse in this order: anything already deteriorating, unidentified photos of people only one elderly relative can name, one-of-a-kind items, and then everything else.
• Interview while you scan. Sit with an older relative and record what they say about each photo; those identifications are worth more than any sleeve.
• Buy enclosures by the standard, not the label. Look for "passes the PAT" and "acid-free, lignin-free" rather than vague words like "archival" or "photo safe."
• Keep the context. Note which album, box, or envelope each photo came from; groupings help date and identify photos later.
• Write a one-page guide for your heirs. Say what the collection is, where the backups are, and which archive should get it if no one in the family wants it.

Frequently Asked Questions

What is the best way to store old photographs at home?

Put each photo in a sleeve or folder that passes the Photographic Activity Test, place the sleeves in a lidded acid-free, lignin-free box, and keep the box in a cool, dry, dark closet in the main part of the house, ideally at about 70°F or below and 30–50% relative humidity. Avoid attics, basements, garages, and magnetic albums.

Are plastic photo sleeves safe for old photos?

Sleeves made of uncoated polyester, polypropylene, or polyethylene are safe for most prints, while PVC (vinyl) sleeves are not. Use PAT-passed paper enclosures instead for flaking or tacky photos, for nitrate or acetate negatives, and anywhere humidity may run high.

What resolution should I scan old photos at?

The Library of Congress suggests 300 dpi for ordinary 4x6 and 5x7 prints and documents, and 400 to 600 dpi if you may enlarge them. Scanning small prints at 600 ppi is a safe default, and slides and 35mm negatives need about 1,900 ppi or more.

Should I wear cotton gloves to handle old photos?

Clean, dry hands are fine for most prints if you hold them by the edges. The Library of Congress recommends clean nitrile gloves when gloves are used, especially for tintypes, glass plates, and film negatives. Never touch the image surface.

How do I get photos out of a magnetic album?

Photograph each page first, then try sliding a thin spatula or unwaxed dental floss behind a corner. If a print will not release easily, stop and scan the page with the photo in place; forcing it can tear the print, and a conservator can remove stubborn photos safely.