Recently, a client who purchased a Sony PMW-F3 from AbelCine gave me a call with a “quick question”. He had just updated his camera with the S-Log recording option and discovered that he could now set his camera’s sensitivity in a number of different ways. He could set the camera’s gain, ISO or, with the S-Log mode turned on, he could set an Exposure Index (EI). He wanted to know the difference between these settings, and which was best to use.