The bag containing the memory card was discovered it in a walkway alongside the River Wandle in the Haslemere Industrial Estate just before Christmas.
Detective Constable Riaz Karolia of Wimbledon Police said:
"So far we have had no success in locating the owner of this bag. I am hoping that by issuing these images, someone may recognise the people involved and we can start the process of reuniting the owner with their belongings.
"The memory card contains images of someone's special day - if you know who these people are, please get in touch."
More top news
Four out of five puppies - three girls and a boy - were born safely, although one sadly died.
Commuters now find their daily rush hour struggle is more stressful than going to the dentist or moving house, a major new survey reveals.
Leonie Granger deliberately targeted Mehmet Hassan, who was robbed and kicked to death by two men she let into his flat.