The Camera (Canon Rebel T3)

• Parallax- occurs when the viewfinder or viewing lens is seperated from the taking lens.
• Pentaprism- is a five-sided reflecting prisim used to deviate a beam of light by 90°.
• Pellicle Mirror- is an ultra-thin, ultra-lightweight semi-transparent mirror employed in the light path of an optical instrument, splitting the light beam into two separate beams, both of reduced light intensity.
• 
  
  Digital SLR- digital cameras that use a mechanical mirror system and pentaprism to direct light from the lens to an optical viewfinder on the back of the camera.

•  Aperture- is a hole or an opening through which light travels.
Shutter- a photographic device that administers the exposure by limiting the time over which light is admitted.
Exposure- the total amount of light allowed to fall on the sensor during the taking of a photograph.
Depth of field- is the distance between the nearest and farthest objects in a scene that appear acceptably sharp in an image.
F-Number (or focal ratio, f-ratio, f-stop, or relative aperture) of an optical system expresses the diameter of the entrance pupil in terms of the focal length of the lens; in simpler terms, the f-number is the focal length divided by the "effective" aperture diameter.
Focal length- of an optical system is a measure of how strongly the system converges (focuses) or diverges (defocuses) light.