The Sony Alpha DSLR cameras offer a great deal of customization so the user can use it the way he/she wants it to. Customizing the camera to your preference can result in a faster operation.
One function that allows customization is the Control Dial Setup.
Dial Or Dials?
The purpose of the dial(s) in your Alpha DSLR is/are to change either shutter speed or aperture number.
Depending on what model you've got, you may have 1 or 2 dials:
A100/200/300/350: 1 dial
A700/900: 2 dials
For the cameras with 1 dial, you can move one setting with it, with cameras with 2 dials, you control each setting with each dial.
But the good news is, if you got 1 dial, you can pick which setting to move, and if you got 2 dials, you can chose where you want the settings.
Choosing your weapon of choice
You may wonder: "Why do I need to change the setting on the dial or the order they are arranged?"
The answer is: Customization
Customizing something means that its designed or set in a particular way thats not usually the normal way.
If you change the steering wheel of your car for a sports steering wheel, that would be one example of customization. You're making the item more comfortable for YOUR use, and the more comfortable you're with an item while using it, your control and performance increases.
And this is what you're aiming at with a camera.
There are photographers who like to use the shutter speed more than aperture (like sports photographers) and viceversa(like portrait photographers). Or they use both but they give preference to aperture and they need it more handy than shutter speed.
If you got 1 dial in your Alpha DSLR, you will have to pick which setting you use or will use the most: shutter speed or aperture. The default setting is shutter speed.
If you got 2 dials, you can select to have shutter speed in the front and aperture in the back dial or viceversa.
To have these two important settings the way you want them to will give you a faster access to them when you're shooting.
Invoking the Control Dial Setup.
To set which value to change or in what order the values are arranged, you need to do the following:
A100: Menu->Custom (clockwork icon) Menu Page 2->Ctrl Dial Set->Shutter Speed or Aperture
A200/300/350: Menu->Custom (clockwork icon) Menu Page 1->Ctrl Dial Set->Shutter Speed or Aperture (These cameras have just one page for the Custom Menu, so you can't miss it)
A700/900: Menu->Custom (clockwork icon) Menu Page 2->Ctrl Dial Set->Front SS/Rear F/no or Front F/no/Rear SS
SS= Shutter Speed
F/no= F number
Notes Of Use.
In the Alpha 100/200/300/350 to use the other setting the dial doesn't immediately control, you need to press the Exposure Compensation button (the one with the square with the plus and minus icons).
You chose Shutter speed to be controlled by the dial, which means you will need to press the Exposure Compensation button and move the dial to control the aperture. If you set aperture to be controlled by the dial, you will need to press the Exposure Compensation button and move the dial to control shutter speed. You need to keep the button pressed while moving the dial.
In Alpha 700/900 its best to control the rear dial with your thumb, since is the finger closest to that dial, moving another finger may require you to pay attention to what youre doing, and what you want is seamless control while shooting. Although if you feel more comfortable using another finger, go ahead :)
Learning to use your camera is utterly important, but just as important is that you set it the way you feel most comfortable with it in order to improve your response time and performance while using it.
The Sony Alpha DSLRs give you plenty of customization, that means you got options to chose from, USE THEM!