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."
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The 47-year-old man died shortly after 3pm on Tuesday.
Specialist explosive detection dogs searched through the town examining letter boxes and phone booths for signs of potential devices.
Temperatures reached 29.1C in St James's Park, central London.