examples of lenses for portraits and their background blurring capabilities

see also:

• portrait lenses
• depth of field (DOF)
• depth of field comparisons for portraiture

• almost anyone with a point and shoot camera can take a portrait where everything is almost on focus, but generally, the better portraits which emphasise the face need the background to be nicely blurred and this is where your special portrait lens comes in - you really need an aperture f/2.8 or wider and a 35mm effective focal length in the 70-140mm range, and preferably a circular diaphragm for nice background blurring.
• in other words, the kit lenses supplied with most cameras are just not good enough for nice portraits with blurred backgrounds.
• background blurring is largely dependent on aperture and actual focal length, while the aesthetics is also dependent on how circular the iris diaphragm is (the Olympus ZD lenses have circular diaphragms for very nice bokeh).
• these series of images were all taken hand held and varying distances to try to keep the mannequin in a similar torso shot, all using ambient light, and primarily to demonstrate the effect of each lens on perspective (watch the amount of background visible) as well as the degree of blurring of the background and the aesthetic quality of the blurring of the background (bokeh).
• I have tried to approximately keep the mannequin as same proportion in each image taking into account the Canon has a different aspect ratio to the Olympus images which are shorter but wider.
• apologies for the mannequin I borrowed from a nursing school.
• let's have a brief look at the lenses:
  • the Olympus kit lenses, whilst perhaps the best kit lenses out there in terms of optical quality, are not great portrait lenses as their apertures are restricted to only f/3.5, thus an Olympus user wanting a portrait lens should consider either:
    • Olympus ZD 50mm f/2.0 macro - a very sharp macro lens
    • Olympus ZD 50-200mm f/2.8-3.5 - a very versatile lens
    • or, if on a budget, try a manual focus lens such as an Olympus OM 50mm f/1.4 but older style diaphragm shape will give hexagonal out-of-focus highlights, not circular.
  • the Canon 24-105mm f/4L IS lens, whilst very versatile, does not make a great portrait lens but is passable at 105mm f/4 which gives a similar effect to a 50mm f/3.2 lens on an Olympus, and thus the Olympus 50mm f/2.0 macro and the Olympus 50-200mm f/2.8-3.5 are better portrait lenses.
  • fortunately for Canon users, there are two relatively inexpensive AF solutions which give excellent portrait results:
    • Canon EF 50mm f/1.4 or f/1.8 lens - particularly if using a APS-C Canon with 1.6x crop factor
    • Canon EF 85mm f/1.8 lens - particularly if using a APS-H Canon (1.3x crop) or a full frame.
    • similar options are available for Nikon, Pentax and Sony users.
  • for my mind though, of all these lenses, the winners for portraits are:
    • if need shorter focal length for space reasons:
      • Canon EF 85mm f/1.8 at f/1.8
      • Olympus ZD 50mm f/2.0 macro
      • Canon EF 50mm f/1.8 or f/1.4 on an APS-C 1.6x crop Canon only
    • if can get away with being a bit further away:
      • Canon EF 135mm f/2.0L at f/2.0 
      • Olympus ZD 50-200mm f/2.8-3.5 at 100mm, f/3.3 or can even go to 200mm f/3.5 for a very beautiful effect
    • see bottom of page for direct comparisons of each wide open.
  • of course there are great other options such as:
    • Olympus m.ZD 45mm f/1.8 portrait lens and Olympus m.ZD 75mm f/1.8 lens for Micro Four Thirds system
    • the very cheap but brilliant Samyang / Rokinon 85mm f/1.4 lenses
    • more expensive 50mm f/1.2 and 85mm f/1.2 or f/1.4 lenses, or in the case of Olympus Four Thirds dSLR system, the superb Olympus ZD 35-100mm f/2.0 lens
    • Canon EF 70-200mm f/2.8L - but big, heavy and expensive and too long for a 1.6x crop camera
    • tilt-shift lenses but these are a bit complicated to use and expensive.
• I have also included some wide angle shots to show the change in perspective obtained and the exaggeration of facial features as the camera gets closer.
• the eq. focal lengths mentioned below are the equivalent focal length in 35mm terms when accounting for the crop factor of the sensor.

NB. remember, Olympus lenses have a 2x crop factor while the Canon ones were tested on a Canon1DMIII with 1.3x crop.

Canon EF 50mm at f/1.8	Canon EF 85mm f/1.8	Olympus ZD 50mm f/2.0 macro
Canon 135mm f/2.0L	Olympus ZD 50-200mm at 130mm f/3.3 of course, you could stand even further back and use this lens at 200mm f/3.5 for even better background control with beautiful bokeh.	Olympus ZD 50-200mm at 96mm f/3.2
Canon 24-105mm f/4 IS L at 105mm f/4 a very versatile lens but there are better lenses for portraits	Olympus ZD 14-42mm kit lens at 42mm f/5.6 this is a great kit lens, but just not for portraits	Olympus ZD 40-150mm kit lens at 98mm f/5 passable for portraits but at 200mm eq. focal length

And comparison with different apertures and focal lengths:

Lens	f/1.8-f/2.0	f/2.8-3.3	f/4-4.5	f/5.6
Olympus ZD kit lens 14-42mm f/3.5-5.6			Olympus ZD kit lens at 14mm = 28mm eq. at f/4	Olympus ZD kit lens at 42mm = 84mm eq. at f/5.6
Olympus ZD kit lens 40-150mm f/4-5.6			Olympus ZD 40-150mm kit lens at 40mm = 80mm eq. at f/4 Olympus ZD 40-150mm kit lens at 98mm = 196mm eq. at f/5	Olympus ZD 40-150mm kit lens at 40mm = 80mm eq. at f/5.6 Olympus ZD 40-150mm kit lens at 98mm = 196mm eq. at f/5.6 Olympus ZD 40-150mm kit lens at 150mm = 300mm at f/5.6
Olympus ZD 50mm f/2.0 macro	Olympus ZD 50mm f/2.0 macro at f/2.0 (=100mm eq.)	Olympus ZD 50mm f/2.0 macro at f/2.8	Olympus ZD 50mm f/2.0 macro at f/4
Canon EF 50mm f/1.8II with 1.3x crop sensor	Canon EF 50mm f/1.8II at f/1.8 (= 65mm eq)	Canon EF 50mm f/1.8II at f/2.8	Canon EF 50mm f/1.8II at f/4
Canon EF 85mm f/1.8 with 1.3x crop sensor	Canon EF 85mm f/1.8 at f/1.8 (= 111mm eq)	Canon EF 85mm f/1.8 at f/2.8	Canon EF 85mm f/1.8 at f/4	Canon EF 85mm f/1.8 at f/5.6
Canon EF 135mm f/2.0L with 1.3x crop sensor	Canon EF 135mm f/2.0L at f/2	Canon EF 135mm f/2.0L at f/2.8	Canon EF 135mm f/2.0L at f/4
Canon EF 24-105mm f/4 IS L with 1.3x crop sensor			Canon EF 24-105mm at 105mm = 137mm eq. f/4  Canon EF 24-105mm at 50mm = 65mm eq. f/4 Canon EF 24-105mm at 24mm = 32mm eq. f/4	Canon EF 24-105mm at 105mm f/5.6
Olympus ZD 50-200mm f/2.8-3.5 SWD		Olympus ZD 50-200mm at 50mm = 100mm eq. f/2.8 Olympus ZD 50-200mm at 96mm = 192mm eq. f/3.2 Olympus ZD 50-200mm at 130mm = 260mm eq. f/3.3	Olympus ZD 50-200mm at 50mm f/4 Olympus ZD 50-200mm at 96mm f/4 Olympus ZD 50-200mm at 130mm f/4
Olympus ZD 7-14mm f/4 ultrawide			Olympus ZD 7-14mm at 7mm = 14mm eq. f/4 Olympus ZD 7-14mm at 14mm = 28mm eq f/4

And, just for fun, here is what the Olympus 7-14mm lens can do a bit closer - really exaggerate the features:

Here is what you can do with a Canon 1DMIII, 85mm f/1.8 lens at f/2.8, Westcott umbrella softbox and 2 gelled flash guns to turn day into night: