« on: December 20, 2012, 03:40:53 PM »
There's some bad advice being given here.
If you use manual exposure, make sure auto ISO is turned off. When auto ISO is turned on, your camera changes the ISO to obtain what it thinks is proper exposure, so all your work with shutter speed and aperture is undone.
I disagree. There are times when manual + auto iso is the way to go. If you want to set a fast shutter AND control depth of field AND have the camera meter... auto iso is the way to go.
Real world example: I was shooting a pro motocross race. I set a specific shutter speed that balances motion blur with stopping action. I set aperture to 5.6 (on 70-200 f/2.8 IS II) because it's outdoors with hills and crowds in the background and I don't want them blurred to nothing. Also the extra depth of field helps fudge focusing accuracy on fast moving riders. In some areas they move from open track to the shade under trees causing the lighting on them to change, so I used Auto ISO to allow the camera to meter and expose them correctly. It worked like a champ.