Many Options

• Many lens options exist for the photographer shooting portraits. The choice boils down to the type of portrait the photographer seeks to capture. For example an environmental portrait might require showing much of the scene around your human subject. In this example a wide angle zoom lens such as the Canon EF 17-40 mm f/4L USM might work best. Another example is the close-up portrait of a new born baby. The photographer could choose a lens such as the Canon EF 100 mm f/2 USM in that instance. In summary, lens choice depends upon the final image the photographer or client wishes to portray.
  
  

Classic Portrait Lenses

• Lenses with focal lengths between 85 mm and 105 mm make up the classic portrait lens range for 35 mm film and full frame digital cameras. Also, portrait photographers traditionally stayed away from using zoom lenses and used fixed focal length lenses. Fixed focal length lenses inherently have a greater degree of sharpness and color saturation than zoom lenses. In this category, a photographer might choose the Canon 85 mm f/1.2L II USM, the 85 mm f/1.8 USM or the 100 mm f/2 USM. These lenses have wide maximum apertures that provide shallow depth of field and also allows the photographer to shoot under less than optimal lighting conditions.
  
  

APS-C Lens Options

• Because Canon's APS-C cameras have a crop factor of 1.6x photographers must multiply the focal length of any lens used by the crop factor. So lenses that are traditionally wider than the standard portrait lens focal length are now available options for creating portrait images. For example, Canon's standard 50 mm lens when used on a camera such as the Canon T3i has an effective focal length of 80 mm. This places the lens very close to the traditional portrait lens range.
  
  

Zoom Lens Options

• Many photography enthusiasts balk at the expense of fixed focal length lenses and super expenses zoom lenses. Also, because most non-commercial photographers use APS-C cameras Canon has a number of zoom lens options that fall into the portrait lens range. These include the standard 18-55 mm lens that comes with most APS-C cameras. Because of the crop factor, this lens functions as an 88 mm lens at its longest focal length. Other options include the EF-S 15-85 mm f/3.5-5.6 IS USM, the EF-S 18-135 mm f/3.5-5.6 IS and the 18-200 mm f/3.5-5.6 IS lens.