Primal scream photo portraits captured with Triggertrap sound trigger app

It's important to capture emotion in a portrait but how about photographing a good, old-fashioned primal scream? With a free, sound-triggering iOS app and an attached dongle, all you need is a visceral scream to create one of these powerful portraits with your digital SLR.

The folks from Triggertrap, which created the app (called Triggertrap Mobile) and the dongle ($30), demonstrated the technology recently at a "ScreamGrab" photo booth at the Mini Maker Faire in London.

Triggertrap Mobile lets you fire the shutter of your DSLR in several ways including via a "Bang" sound trigger, which is what was used for the ScreamGrab photo booth. (Other Triggertrap functions include Timelapse, DistanceLapse, and Long-Exposure HDR.)

For the ScreamGrab photo booth, an iPhone with the attached dongle was synced to a DSLR on a tripod. Then Faire attendees shouted or screamed in the booth, which created the primal scream "self" portraits. As you can see from the below images, kids seemed to have the most fun with the photos but adults certainly "let it all out" as well.

See more of the scream portraits here. Read our 2012 review of Triggertrap here.