Just about every photography app from Photoshop to iPhone freebies uses a histogram to represent the colour properties of the image to be edited. Just about no one understands what they’re looking at…

I’ve been using Photoshop since it’s very first version and an instructor for nearly 20 years but there are some things in Photoshop (and Lightroom and so many others) that are just plain confusing and yet they’re completely fundamental to how it works. In this post, we’ll look at histograms because they really are the first thing you come across in any work involving image correction or adjustment.

Forget the Colour

Just for a moment, let’s disregard the individual colour channels that go into making an image and focus instead on the overall light volume (or value or luminance or brightness or tone).