Camera Tools

 

A quick look at image histograms is the starting point to understand image exposure weaknesses and how to correct them.

 

In an image recorded in 8 bits we find 256 discrete brightness values, from absolute black (0) to pure white (255). Histogram horizontal axis covers the range from 0 to 255. Histogram height tells how many pixels or how much of the image is at any particular brightness level.

 

Four graphs are displayed: RGB/Luminance (a touch on the small blue label above the grey graph will toggle between luminance and RGB histogram), Red, Green, Blue.

 

Tip: A well exposed image should show a mountain shaped histogram,

spanning from left to right without peaks at the very ends.