I've just read something in Bryan Peterson's Understanding Exposure the next scenario:
- he was photo'ing a landscape and wanted to get everything sharp.
- he point the camera to the sky above to get his reading with the aperture set to 2.8 i think.
the camera says that a (let's say) 1/200s is needed to get the corect exposure
- he wants to get everything sharp remember ? so he calculates that from 2.8 aperture to 16 aperture there are like 5-6 stops so he sets his aperture to f16 and then lenghten the time accordingly.
- he shoots the landscape.
now -why, while taking the light reading from the sky, didn't he use the f16 aperture right from the beginning ? would he have got a different results regarding shutter speed ?
please, excuse my bad english.