Using the Histogram

Using the Histogram

Basic Explanation: your histogram gives you a graphic depiction of the data you’ve captured.

Understanding Shadows vs. Highlights – your histogram has five sections to it. The far left is black, the far right is white, and dead center is 18% gray, the data that falls to the left of center is shadow, and the data that falls to the right of center is highlights.

When you pull up your histogram in many editing programs it will also give you specific color information.

Clipping – clipping is when your data goes off the chart to either the right or left. You have ‘clipped’ off information…there is no data recorded. Some cameras will actually have a flashing mechanism on your view screen when there is no data to display. This will print as either pure white or pure black.

Mountain range & spikes – your goal is to have bell shapes and spikes on your histogram. If there is a lot of any one color especially high key (white) or low key (black) you should have spikes in either the right or left regions of your histogram. Most images that have lots of color should have a mountain range effect on your histogram. This means that you have solid data in all color zones.

Under exposing and over exposing – If your histogram is heavily weighted like a bell curve to one side or another and may have clipping to that extreme side…you are either over or under exposing your images.

Exposing for Shadow vs. Highlights – in the day of film most photographers exposed for the shadow and at the beginning of the digital age they did the same thing. Current thoughts are either to get a clean exposure across the board or to expose for the highlights…so your histogram will have a more mountainous appearance to the right of center vs. left of center.

I can fix it later attitude – contrary to what many people believe, it is not all that easy to ‘fix’ under or over exposed images in postproduction. If you have under exposed an image and pull it into a editing software and try to brighten the image many times you will end up with a pixilated image. This is because the software is trying to fill in information that just isn’t there, it is trying to add light…so it is filling it with noise.

A strange thing happens on the opposite end. If you have blown out all the detail in your whites and attempt to use your editing software to fix it…you are trying to take out light and add detail where there is none. So what will the software do? It will fill it with varying degrees of gray, which gives you a muddy photo.

Fix it in your camera that’s why they have the view screen and the histogram read outs. It gives you a chance to get your settings right the first time!