Q. How do I reference a photograph that either I or a colleague have taken?

It is recommended that you follow the guidelines on page 11 of the Harvard Referencing Handbook (omitting the publication information):

• Photographer (surname, initials)
• Year photograph was taken in round brackets
• Description of photograph in italics
• photograph in square brackets, followed by a full stop
• Private collection followed by a full stop 

e.g. Smith, G. (2018) Celebrating diversity [photograph]. Private collection.