Preserve the arrangement
Keep the full collage with its caption and page URL. Then make separate copies of each panel without adding or removing content inside the panel itself. Number the panels so later notes remain easy to follow.
Review panel by panel
- Search each picture independently.
- Record a candidate source for that panel only.
- Compare dates and captions across panels.
- Check whether the collage's combined claim follows from those sources.
A “before and after” collage may use genuine photographs taken in different locations or under different conditions. Finding both pictures helps assess that relationship, but neither match alone verifies the advertised transformation.
Avoid a shared-origin assumption
Do not apply the credit from one panel to all the others. If a panel remains unresolved, mark it separately. A useful result may show that the collage is a composite of distinct publications without revealing who assembled it or why.
Continue with tracing an original source.