Here's how: 1  Stand with your feet shoulder-width apart and knees bent slightly. 2  Lean forward, placing your hands just above your knees. 3  Round your back so that your chest is closed and your shoulders are curved forward.  Then arch your back so that your chest opens and your shoulders roll 1  back. Repeat several times.
Typically this count is between 100,000 and 300,000 shutter actuations, with the latter limit associated with the EOS-1D models. In fact, the Camera Shutter Life Expectancy Database is a really neat user-based site for DSLR models of several brands, including Canon.
Shutter Speeds. A slow shutter speed refers to leaving the shutter open for a long period of timeâlike 1/30 of a second or longer. A fast shutter speed means that the shutter is open for a very short period of timeâlike 1/250 of a second or less. When to use Shutter Priority (Tv) mode When working with fast-moving subjects where you want to freeze the action ; much more on this in Chapter 5