Program mode – one step above auto: In Program mode your camera will set the aperture and shutter speed. You control your ISO, exposure compensation and other settings. You will also notice your pop up flash will not automatically pop up as it does in auto mode. What is ISO? This is the cameras sensitivity to light. To produce noise free images its best to use your camera at the lowest ISO. In Program mode practice changing your ISO from lowest 100 to highest. As you do this watch your A and S change. Also look at the difference in the light or exposure of your images.
Program Shift: Program Shift is useful because it lets a camera users creativity come into play in a simple and reliable way. It makes the selection of various aperture and shutter speed combinations easier for the photographer, while still ensuring accurate exposure. For instance, a scene can be photographed with an f-number of f/2.8 and a shutter speed of 1/500 seconds. It can also be shot with an f-number of f/5.6 and a shutter speed of 1/125 seconds. The first settings combination allows for a shallow depth of field and makes it easier to photograph moving subjects. On the other hand, the latter settings ensure that more of the scene is in focus. But both images will be exposed similarly.
The appearance of blurriness in the background or foreground is generated when the aperture is wide open. When you open up the aperture, more light hits the sensor, the camera compensates by speeding up the shutter. When the aperture is closed down (or stopped down), the shutter has to stay open longer.
If the lighting conditions are too dark or too light, you could select an aperture setting such that the camera may not be capable of a shutter speed slow enough or fast enough to take the picture. This requires you to back off the aperture setting until the camera can pull it off. By that time you get it right, the moment could be gone. There is a way to approach this that guarantees that your camera can take the picture. It works while the camera is in Program mode and it is called Program Shift.
With program shift you press the shutter button half way so the camera can focus and calculate a suitable aperture setting and complementary shutter speed. Next, you rotate the wheel next to the shutter button (while keeping the shutter release button pressed half-way; it’s tricky). What this does is increase or decrease the aperture value while simultaneously changing the shutter speed. Since the camera knows how much light is available, the camera stops you from selecting an aperture setting that won’t work.
Check your manual for camera-specific instructions for using this very powerful, often overlooked, tool for photographers who want more control than offered by full automatic mode.