This is a slight rework of a post I made on an old blog back in 2011, with a bit of an update to elaborate on a couple of points.
Originally this was in response to an article written by a particularly well known photographer claiming to “bust” some myths that his article actually end up reinforcing and propagating (which might explain why his post now seems to have magically vanished from the web).
I’d had a little back and forth on Twitter with this person regarding his new article and why PPI doesn’t matter when resizing images for digital display (meaning, on the screen, on the web, via digital projector running off a laptop, via a mobile device, whatever) which he claimed was a myth, and that it does matter.
During my talk for Lancaster Photographic Society recently, I was asked a question that I’m also going to answer here. I’m paraphrasing, but it went something along the lines of…
“Is getting the right exposure in camera really all that important? Can’t we just nudge it in Photoshop?”
Before I start, I want to clarify a definition here, and a difference between “right” and “technically correct”. It is perfectly possible to make an exposure that is “right”, but not “technically correct” when you shoot with your post processing in mind in order to maximise the capabilities of your camera’s sensor.
Sometimes intentionally over or underexposing slightly allows you to capture the scene and process it in a way that gives a better final result than if you’d started off with a “technically correct” exposure. So, sometimes “technically correct” isn’t the same as “right”.
But to answer to the question, the short answer is “You can, but if you don’t have to, why would you?”.