SIMON RINGSMUTH, DIGITAL PHOTOGRAPHY SCHOOL:
"Almost every DSLR or Mirrorless camera has a mode dial with a variety of letters and icons on it, some of which might seem cryptic or confusing. Usually you’ll find a green icon for Full Auto mode (usually a green A or rectangle), Full Manual mode (M), as well as Aperture Priority (A or Av) and Shutter Priority (S or Tv). Your camera might also feature scene modes such as portrait, night, or macro, and even some user-configurable modes indicated with a U1 or U2 (or C1/C2, etc.)
"Somewhere on that dial is a letter that’s often left neglected, and unused by many people, even though it can be quite powerful – Program Auto (P). In my experience most people don’t use it because they don’t understand it. Is it Auto? Is it Manual? What can it do that the other modes can’t? The answer is a bit strange at first, but once you wrap your head around what the humble little P mode can do, you might find yourself using it much more than you thought."
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