MACRO LENSES

What is the best lens for taking medical pictures in the operating room and is this type of lens suitable for other purposes (portrait, etc). I have a Canon 20D

I know someone who has the EF100 f/2.8 for taking dentistry photos, saves him having to get too close

Depends on the amount of subject material you are trying to capture.

A good macro will let you get 1:1 or beyond. However, a 100mm will be a narrow view. If you want shots of the patient or medical staff performing the procedure, something much wider may be needed.

100 mm is a on the long side for portraits unless they are head and shoulder, but most macro lens are very sharp, so they are well suited to this.

I use my 105 Sigma often for "people" shots when I want to keep some distance or be discreet, but it would not work for that in close quarters.