The box in the loft has two problems and they are not equally urgent.

The photographs are deteriorating slowly. That is a real problem and it will take decades.

Nobody knows who the people are. That is a problem with a much shorter deadline, because it is solved entirely by asking a person who is currently alive.

Do the identification first. A perfectly preserved photograph of an unidentified woman is an object. A creased photograph with “Ada, my mother’s sister, Scarborough 1931” on the back is a record.

Start with the identification session

Take the box to the oldest person who might know, and take a soft pencil.

Work in short sittings. An hour is plenty, and enthusiasm drops sharply after that. Put anything they cannot identify to one side rather than labouring over it; there is often a second person who will know.

Ask more than the name. “Who is this” gets you a name. These get you the record:

Who is this, and how are they related to me?
Where was this taken?
Roughly when? A decade is fine.
What was happening that day?
Who took it?
Who else was there but not in the picture?

Write short answers immediately, on the back, in pencil. Long answers go on a separate sheet with a number that matches a number on the photograph. Do not trust yourself to remember which picture a story belonged to; you will not.

If the person who knows is difficult to get talking, photographs are the best tool you have and worth using deliberately: what to do when a relative will not talk. A gathering is the other high-yield setting, because the room can argue its way to an answer.

What to write with, and what not to

Use a soft pencil, 2B or softer. It writes on most photographic backs without pressure and it can be corrected. This is the standard recommendation from archives and it is right.

Write in the margin or the edge, lightly, supporting the photograph on a hard flat surface. Never press.

Do not use a ballpoint. It requires pressure that embosses through to the image.

Do not use a marker or permanent felt tip. The ink can migrate through the paper and it will eventually appear on the front. This is the most common way of ruining a photograph while trying to look after it.

Do not use sticky labels or ordinary sticky tape. Adhesives are among the worst things you can attach to a photograph.

For modern resin-coated prints that pencil will not take, write on an acid-free sleeve or an enclosure rather than on the print.

What to write

Keep it to a consistent shape so a stranger can read it in fifty years:

Who, relationship to a named anchor person, where, when, source of the information

For example: Ada Whitfield, sister of my grandmother Elsie. Scarborough, c. 1931. Identified by Elsie, 2026.

Two details people leave out and should not:

Anchor the relationship to a named person, not to yourself. “My great aunt” is meaningless once the photograph outlives you. “Sister of Elsie Whitfield” survives.

Record who identified it and when. This is what separates a fact from a guess later, and it lets a future relative weigh two contradictory labels.

If you are unsure, say so on the label. Probably Ada is honest and useful. Ada is a fabrication that will be repeated as fact forever.

Scanning, once

Scan at 600 dpi for ordinary prints. It is enough for large reprints and it is not so large that you abandon the job halfway.

For negatives, slides or very small prints, go higher, 1200 to 2400 dpi, because you are enlarging.

Save each scan twice: an unedited master, and a copy you may crop or correct. Never edit the only version.

Use TIFF or PNG for masters if you can and JPEG for the copies you share. If a phone scanning app is the difference between doing this and not doing it, use the phone app. A photographed photograph on a table by a window, without flash, is far better than nothing and takes an afternoon rather than a month.

Name the files so the name carries the information: 1931-c-scarborough-ada-whitfield-01.tif. Photographs get separated from spreadsheets. Filenames travel with the file.

Storing what you keep

The four things that damage photographs are light, heat, damp and acid. Handle those and you have done nearly all of it.

Not the loft, not the garage, not the cellar. Temperature swings and damp are the main killers, and those are the three places families store photographs. A cupboard in a bedroom is better than any of them.
Cool, dark, dry, and stable. Stability matters more than achieving any particular temperature.
Acid-free boxes and sleeves. They are inexpensive and they are the single best purchase in this whole area.
Get rid of the magnetic albums. The self-adhesive ones with a plastic sheet over the page are actively damaging and the adhesive becomes irreversible over time. Removing photographs from them is a genuine priority if you have any.
Do not laminate anything, ever.
Separate the very old ones, particularly anything on glass, tin, or with a paper mount. If you have something that looks unusual, ask an archive before doing anything to it. Most county record offices will answer a polite email.

Two copies, two places

The scans are the version most likely to survive a fire, a flood or a house clearance, and they are worthless if they live in one place.

Keep one copy on a drive you own and one somewhere else: a cloud account, or a second drive at a relative’s house. Check the drive still opens once a year. Storage fails silently and usually at the moment it is needed.

What to do with the ones nobody can identify

Do not throw them away, and do not spend a year on them.

Put them in one clearly marked box: Unidentified, asked Elsie 2026. Note who you have already asked, so the next person does not repeat the work. Photograph or scan them and send the batch round the wider family once. Cousins and in-laws know things that the direct line does not.

Some of them will be identified at a funeral, oddly enough, when relatives meet who have not met in years.

The point of doing it at all

A named photograph with a sentence on the back does something a scan cannot. It gives a person back their name and puts them somewhere, on a particular street, in a particular year, in a family that still exists.

That is the same job as the rest of this work, done in one line rather than a thousand words. If the photographs are prompting stories as you go, write those down too, and consider what form the whole thing should eventually take: what to do with a finished family journal.