Alasdair Baxter wrote in
:

I have an old school photograph which was taken with a panning camera
resulting in a very long narrow strip.

I tried Jessops and Boots to get a copy made but they refused on the
ground that it was copyright.

Fair enough, but this was taken about fifty years ago and there's no
photographer's name on the print so I don't know how to set about
getting copyright clearance. Even if the photographer is dead and
gone or, being a company, has been dissolved, the copyright apparently
subsists for 75 years after the death of the photographer or the
demise of the company.

Who owns the copyright? Normally the creator of the work holds the
copyrights, but this isn't always the case, especially with commissioned
pieces. Perhaps the school owns the copyright?

Have you tried contacting the school and asking them who the photographer
was?

Once you have made some efort to find the photographer you could try taking
those documents to [some photograph developing place] and asking them if
they'll do it. You're only after one copy?

You could also try saying that you need a copy for private research and
study, and that this is non-commercial private research and study, and that
you are allowed to make a copy under "fair dealing".