The Fallacy of the Histogram

Photography

People always say: “If you want to know if you are exposing correctly, check the histogram and shoot to the right”.

What’s the histogram? The histogram is the graph representation of the tonal distribution of your photo, kind of. The histogram shows the number of pixels for each tonal value from 0 to 255.

Why do I say: “kind of”? Because it’s a fake. The histogram doesn’t show the numbers of pixels for your photo. The histogram shows the numbers of pixels for a “proxy” of your photo. The histogram is for the JPEG preview that is contained in your raw file and that is displayed on the LCD, that is unless you shoot JPEGs when it’s the analysis of the displayed photo.

As everybody that uses Lightroom knows, there’s a huge difference. You can see it when the image in Lightroom is first displayed and then change.

Warning

  • The histogram will depend on how bright have you set the LCD on your camera.
  • Many photographers set the LCD to manual and level 4, the brightest, which will throw the histogram of quilter.