The Sony A7S is a full frame mirror-less camera that shoots photos and 4K videos in low light. The guys at DigitalRev TV look to find out if the new Sony A7S is a high-end DSLR killer. They find out by testing it’s capacity in the dark versus the Canon 5D Mark III, Sony A7R and the Nikon D4s. The video shows us the results of the test.