Hi all,

I just received my new toy for my Pentax 6x7 (SMC 135 Macro lens). I've been looking for some info on it, without a lot of luck. I have a few questions for anyone who may have some experience with it:

1) There are a series of number around the end of the lens (3.2, 3.5, 3.7...15, 30). What are they for?
2) Sorry if this is a silly question, but what makes this a 'macro' lens? How does a macro lens differ from a regular lens?