How to date a colour slide without inventing a year

A slide mount, film edge, colour shift and processing code can sometimes narrow down a period. Clothes and cars can help, but they can also mislead. A 1970s-looking room was not necessarily photographed in the 1970s.

What clues do you trust most? What clues have fooled you?

When evidence is weak, we prefer “date unknown” to a confident fiction.