Photomarathon UK in Cardiff joined by 400 contestants
Hundreds of budding and professional photographers are snapping away around Cardiff during the city's fifth Photomarathon UK.
Some 400 people signed up for event, which began on Saturday morning at the Wales Millennium Centre in Cardiff Bay.
Participants are challenged to take 12 images on 12 given topics over the course of 12 hours.
Every entrant's work will be presented in a free public exhibition at Cardiff Old Library from Friday, 29 July.
Entrants set out across the city to respond to the 12 creative challenges.
It is the second time the event has been completely digital.
Following the event, every entrant's work will be presented in a free public exhibition at Cardiff Old Library opening on Friday 29 July.
Photographs will be judged by a panel of creative experts and Photomarathon organsiers, who will select winners for each topic as well as an overall first, second and third prize for the best set of 12 photos.
Photomarathons have been around for about 25 years and take place all over the world. The Copenhagen Photomarathon is the longest running event, having started in 1989.
The first Photomarathon UK was held in Cardiff in summer 2004 when 140 people took up the challenge, and the number of participants has continued to grow over the years.