Histograms are handy things. They either confirm that you’ve nailed your exposure or let you instantly see if you need to adjust. But, they can be difficult for newer photographers to understand.
So what is a histogram? Put simply, it’s a representation of the brightness levels in your image. Blacks over on the left, whites on the right, and everything else in between. The higher the spike at a particular point, the more of that brightness there is relative to everything else.
A high spike on the left means lots of blacks and shadows. One on the right means lots of whites and highlights. A big spike in the middle means your image is mostly midtones. None of these are right or wrong.
Despite the myths, there’s no such thing as an “ideal histogram”. It’s like asking what’s an ideal walking speed? If you want to walk faster, you walk faster. If you want to walk slower, you walk slower. Same here. Sometimes you want areas of your image overexposed and blown out. Other times, you want to crush those shadows to pure black.
There is a caveat, which David touches on in the video. The histogram is based off the JPG representation of your image. But, that does usually mean that if the JPG looks good, then the RAW will, usually look good, too.
Of course, you can throw this off wildly if you’re using some crazy colour profile that’s optimised for JPG and video. I made that mistake once. After shooting video, I forgot to change my colour profile back. I used the histogram to meter for a few quick shots instead of my Sekonic. While the JPG files looked good, the RAW files appeared very underexposed on the computer.
If you’ve never used custom colour profiles, then you have nothing to worry about. If you do use flat profiles or other wacky picture styles for video, then be sure to set one of the standard ones before you shoot your stills.
Do you use your histogram to check how your shots metered? If not, is it because you just didn’t know how they worked? Or do you just have another method of metering and checking your images? Let us know in the comments.