idkdc wrote in post #17519212
Right, I remember that. I thought ETTR was a Canon thing, overexpose and bring it down, while Nikon is the opposite, underexpose and bring it up in post. Is this correct?
It's just a general technique for getting good signal-to-noise from the sensor and fine gradations in the digital image. AFAIU it should be applicable to just about any sensor or brand.
As AJS has noted - it's about setting desired highlights just below saturation. I.e. put the brightest detail you want to keep as far to the right of the histogram as possible. That way, you'll drag the best possible quality from the sensor, whilst keeping the highlights you wanted. How much (usable) shadow detail you get is then a function of the system's DR.
Obviously if a scene has very low contrast, it's entirely possible it'll look overexposed in camera (i.e. a small range of brightnesses on the histogram, all bunched up to the right). If a scene has wide DR then it's possible the majority of the scene may look underexposed, as putting your chosen highlight at the right of the histogram results in the other detail being a bit dark (i.e. a light in a night street scene). That's not too much of a problem with a sensor with good DR, as you can still recover good detail from the darker areas.