For best Canon portrait lenses read previous post here.

The preferred focal length range for portrait photography is 85-135mm.  To get a blurred background (bokeh), a large aperture is necessary.  For APS-C DSLRs  such as Nikon D90, D40 or D300, this range will correspond to 57-90 mm.  Therefore, the best portrait lenses for Nikon D90, D300 are Nikkor AF 85mm f/1.4D $1069 and Nikon  AF Nikkor 85mm f/1.8D( $450).

Both lenses are very sharp.  Nikon 85mm f/1.4 has an exceptionally smooth bokeh.  Nikon 85mm f/1.8 has great value.

For indoor portrait, or full body portrait, Nikon 50mm f/1.4D AF and Nikon 50mm f/1.8D AF
are the ones to use.  Nikon 50mm f/1.8D AF has great value.

For group portrait, Nikon 17-55mm f/2.8 is needed.  This is one of the best walk around lenses on Nikon D90 and Nikon D300.

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