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Summary: Change ISO setting and shutter speed with main dial. Learn how to use main selection dial for the Canon EOS 40D Digital SLR camera in this free Canon photography lesson.
Ryan Vaughn is a photo enthusiast who has used his expertise for professional wedding portraits and business promotion. He has used Canon's 20D and 30D models as well as the latest...read more
"Okay, now we're moving on to some of the controls with the Canon 40D. We've already established that everything is set up on the camera and ready to shoot. There are two controls on the camera that you will use most of the time, one of them is this main control dial up here on the top of the camera. And it rolls from right to left, and you'll use that for a lot of different things. One of them might be to change ISO setting, the white balance, or your aperture setting, or the shutter speed. And most of the time what will happen is when you're using this main dial is, you can just press like ISO button here on top of the camera, and then move the main dial from right to left in order to change that setting. Right now I'm in fully automatic mode so that ISO setting is not changing at all because it's completely locked in its automatic mode. But if I changed to, if I switched to a different mode, and I pressed the ISO button, I would be able to change that ISO setting with the main dial. Another way to use the main dial, is in the menu options on the camera. If I open up the menu options I can scroll through them from right to left in this menu. And once I get to the end, it's just going to loop back around to the other side. So this main dial, is called the main dial because you will use it probably the most. More than your quick dial which is down here on the back side of the camera. So it's a very useful tool and its right next to the shutter button. You should get use to scrolling back and forth on that thing without even looking at it."
eHow Article: Canon EOS 40D: Main Selection Dial