An old photograph invites a story almost immediately. Before supplying one, spend a few minutes describing what is actually visible. The setting, arrangement and edges of the image can provide useful questions without establishing an identity or date.
Make a separate note for any inscription or information supplied with the photograph. Record where that description came from and whether it refers to the original print or a later copy. A caption is another source to consider, not an automatic explanation.
List possible interpretations after the visual description. Use language that reflects your confidence: visible, reported, possible or unknown. A familiar-looking building or garment can suggest a direction for research without proving the whole scene.
The resulting note may remain brief, but it gives future work a firmer starting point. Careful description protects the photograph from a story attached too quickly and allows later evidence to change the interpretation without losing the original observation.