The canon 100mm f2.8 macro is a fantastic lens (although not an L it should be) it is also an excellent portrait lens. The 50mm f1.8 is an excellent budget prime; ok not as good as the f1.4 version but about a 1/3 of the price. Other lenses that I have used/owned: 17-40mm f4L 70-200 f4L Both are excellent lenses for their intended use, very sharp and contrasty. Also the 28-105mm f3.5-4.5 USM is a very good non L lens, and great value for money. USM is the type of auto focus motor there are 2 types, ring and micro, the ring is the better type and very fast and smooth and almost silent, the micro USM is very quiet and fast bur doesnt allow MF in AF mode, which the ring type does, that may be important for macro work, the Canon 100mm f2.8 macro has the ring USM I cant speak for other brands from experience, but I have heard nothing bad about the Nikon or Sigma counterparts, although the Canon macro is IMO the superior lens over the Sigma 105mm macro for the reasons that Danny stated.

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