PhotoDeCal forum

This past week we talked about the different program modes that are available to determine exposure.  The modes available on most manual-control cameras are:

Program Mode (P): Auto aperture, auto shutter speed, auto/manual ISO, auto exposure

Shutter Priority (S/Tv): Auto aperture, manual shutter speed, auto/manual ISO, auto exposure

Aperture Priority (A/Av): Manual aperture, auto shutter speed, auto/manual ISO, auto exposure

Manual Priority (M): Manual aperture, manual shutter speed, manual ISO, auto exposure

Some discussion questions to think about:

For a given situation, which parameters would you want to control, and which parameters is it OK to let the camera decide?  In what situations would you use each mode (it's OK if you think you wouldn't use a particular mode in any situation).

If you were stuck using one mode all the time, which would it be?  Or if none of these program modes satisfies you, "invent" a program mode of your own with your combination of auto/manual control.

Everyone should make at least one post answering these questions, but feel free to comment on others' posts as well.