4,000 Weddings and Some Funerals is a time-averaged animation created via custom Python code. Images were programmatically “scraped” from Flickr: 4,000 tagged with the word “wedding” and 1,000 tagged with “funeral” posted during June of 2012. The images were then further processed with Python. There was minimal editing; the sequences were determined by download order.
I'm indebted to the still photography work of Idris Khan, Jason Salavon, and Sergio Velázquez for pointing me to this way of combining images.