Understanding Program Shift
Understanding Program Shift: We recently received an email from a student who had trouble understanding the program change. Using a Canon 6D, she puts her camera into program mode, but still has trouble moving it. If you have experienced similar problems, here are some tips:
The program mode works exactly as the auto mode, except the program mode, can replace the exposure projection of the camera. In either of these modes, the camera will attempt to select a moderate aperture and a moderate shutter speed. Remember that the camera has no idea what you are taking a photo or your artistic intention for a particular image. All measure the brightness and reflectivity of the scene.
Let me give you an example: you are pulling outdoors at a wedding. It has a f / 1.4 50mm lens on your camera, and you want to make an innocent gun kill on the face of the bride. There are many potentially distracting elements in the frame, so you want to select a wide aperture to blur the background.
In the program mode, the camera selects a setting of f / 8 and 1 / 125th of a second. By remaining in program mode, the three-stop aperture opens until you see f / 2.8 in the viewfinder. When you open the shutter to allow more light (by decreasing the depth of field to get the blur background you want), the camera automatically moves the shutter speed three stops to 1 / 1000th of a second, so the Exposure remains unchanged.
This is “Program Change”, and works with you by changing the aperture or shutter settings.