Cameras with an APS-C sized sensor are generally not thought of as low-light performers. Despite recent gains in 16 megapixel APS-C technology (NEX-5n, Fuji X-Pro 1), digital noise due to tiny pixels not getting enough light can become a problem at high ISOs starting at about ISO 3200. When packing a 24 megapixel sensor of the same size, these even smaller pixels are all the more susceptible to image degradation. On my NEX-7, I have generally stayed away from low-light (handheld, anyway), simply out of the fear of a low signal-to-noise ratio at high ISOs. But when the job calls for it–an acoustic/electronic music show hosted in a bar–pictures have to be made, so I grabbed my Nikon 50mm f/1.4 S-Auto, and went to work.
To give an idea of the (lack of) stage lighting, this guy’s computer was illuminating him more than anything else in the room!