I've just purchased a pair of 100mm lenses, one is a Nikon Series E manual focus (probably older than me) and the other is a brand new Tokina Macro.
General characteristics are:
- 100mm is fantastic for portraiture;
- They are a lot more forgiving on focus than a 135mm, specially if you are not using a tripod or monopod;
- The Series E is extremely compact and for now is my preferred lens for street portraiture;
- The Tokina is optically superior to almost everything, regardless of price or brand, in this focal length for macro photography;
- Both have an aperture ring (obvious in the case of the Series E), meaning that I can use them on my film body (FA).
I am no specialist on macro photography but am practicing it. The Tokina was a needed addition because though I can focus close with a couple of my lenses, they don't have the magnification of a proper macro lens. In fact, the Sigma 70-200 that I sold was macro capable, but I was tired of carrying that weight around, it was bigger and heavier than 3 of my favorite lenses together (and nowhere nearly as good optically).
Have a look at them. Click to enlarge:
We are going to see a couple of sample portrait shots that I made from 2 of my company's customers. They like photography and allowed me to use the pictures on this post. The body used is a D7000, RAW format converted to B&W. Click to enlarge:
The point here is not to compare the lenses because they are in different leagues and I bought them for distinct purposes. Both are great for portraiture (emphasis on this), both work on my film body, one is compact and stealthy, the other is big and macro capable, but not heavy.
I have a few shots just to test the macro on the Tokina but they are not worth showing, as soon as I have something interesting I will post. If you are also new into it, keep in mind that when focusing close, like 40cm or less, don't even try without a tripod. Even if you have 1/100000 of shutter, camera shake is not the problem, the extremely thin depth of field is. At f16 it is just 3cm or less at this distance, your forward/backward movement will make you miss the focus.
Prices on the Series E vary from place to place and the Tokina you will most likely not find a used one much cheaper than new (if people sell theirs at all), so just buy new.
Thanks for reading and hopefully it was useful in helping you pick a 100m if you are into this focal length.