The Program mode can be used in both the A-REC mode and the M-REC mode. Under the program mode, the camera selects both the aperture and shutter speed. Consequently, you do not have to worry about exposure at all.
When the mode dial is turned to A-REC (see the image below), you are in the program mode.
|The mode dial in A-REC|
If you are in the M-REC mode (see the image below), you may not be in the program mode. This is because the M-REC mode has four exposure mode in total. In fact, the camera will be in the same mode when it was turned off!
|The mode dial|
To enter the program mode when you are in M-REC, hold the MODE button (below left) and turn the command dial (below right).
|The MODE Button||The Command Dial|
While the command dial is being turned, the letter in the lower-left corner of the control panel and the LCD monitor will change (see the images below). The possible letters are P, A, S and M for the program, aperture-priority, shutter-priority and manual exposure modes, respectively. Therefore, once P appears, the camera is in the program mode and you can release the MODE button.
|P for the program mode|
You can use the same procedure to switch to another exposure mode.
When you are in the program mode, the lower corner of the control panel and the LCD monitor display P, meaning the camera is in the program mode. See images below. On the LCD monitor, next to the letter P are the shutter speed and aperture selected by the camera. In the M-REC mode, if autofocus area selection is not turned off (I recommend you do not turn it off as this is a very handy feature), the five autofocus area indicators are also shown. This is perhaps the only significant difference on the LCD monitor that distinguishes the M-REC mode from the A-REC mode.
|Control Panel||LCD monitor (A-REC Mode)||LCD monitor (M-REC Mode)|
The upper left corner of the control panel may display the selected aperture as shown above or the selected shutter speed. You can choose which information to display in both the A-REC mode and the M-REC mode. To make a selection, pressing the MODE button switches the display from aperture (resp., shutter speed) to shutter speed (resp., aperture). Note that if the selected shutter speed is longer than or equal to 1/4 second, it is shown in yellow on the LCD monitor to indicate that noise may appear in the recorded image.
You can use Exposure Compensation to increase or decrease exposure.
As discussed in Exposure Value: EV, when the shutter release button is pressed, the camera meter measures the incoming light and determines an EV (i.e., exposure value). From this EV, the camera selects a proper combination of (aperture, shutter speed). See the image below. You have no way to change this selection; but, you can always use Exposure Compensation to increase or decrease exposure.
In M-REC mode, however, you can turn the command dial to enter the Flexible Program Mode for fine tuning the selection of (aperture,shutter speed).