4:3, 3:2 or 16:9?

I shoot at 3:2 because if I want I can always crop down to 16:9

If you shoot at 16:9 you cannot add the additional info at the top and bottom of the photo.

4:3 is taller thar 3:2 but not as wide

1:1 is the equivalent of 16:9. Except that you loose info that you cannot recover on the sides instead of the top and bottom. You can crop 4:3 down to 1:1

Of course, if you don't like to post process this would add another element to your decision.

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Florida