Noise

The Sony Alpha NEX-7 produces clean JPEGs through ISO 200, and if you look closely you can start to see noise-reduction artifacts starting at ISO 400 (look for halos on the text at ISO 400 and the beginning of detail degradation on the tape measure at ISO 800). That's not to say that the camera produces noisy photos; on the contrary, it generates relatively low-noise images up through ISO 1600. It just overdoes the processing.