Most owners know how to use it, and what it does, but they generally do not know how a Digital Single Lens Reflex camera works. In this article I will explore how a DSLR really works.
Light enters the lens elements, then travels through the aperture. It hits a mirror positioned at exactly forty- five degrees, then bounces up in to the pentaprism. It is bounced to the opposite side of the pentaprism, then through the viewfinder.
This process is taking place every time you have your camera on. When you actually press the shutter button, the mirror swings up to allow the light through. The light that would usually bounce up to the pentaprism is directed to the shutter, which will be open, allowing the picture to hit the sensor, where it is captured. It is temporarily stored in the buffer, before being written to memory card. The shutter then closes, and the mirror returns to its normal position.
An SLT (Single Lens Translucent) uses different technology to a standard DSLR. It has a fixed, translucent mirror that allows two thirds of the light to travel to the sensor, while the remaining third is sent to the viewfinder. Examples of SLT cameras are Sony SLT-A65, A77, A57, etc.
SLT technology has some advantages, such as faster autofocus, and constant visibility during continuous shooting, therefore dramatically improving the ease of panning with movement. Improved video autofocus is also a result of SLT technology.