What is AE?

The Basics:

AE stands for Automatic Exposure and refers to how cameras automatically calculate various settings, such as Aperture, Shutter Speed, and ISO Speed to correctly expose the image.  
AE is used in various shooting modes, from Full Auto, through to Aperture Priority, Program, Shutter Priority, and various Scene Modes. 

The goal of every photographer is to strive towards mastering Manual. Shooting Mode, whereby they can manually adjust various settings to expose the image correctly.
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