100 f/2.8 macro or 100 F/2.0 w/extension tube

I want a 100mm Macro lens. If you put an extension tube on the 100 F/2.0 would the macro quality be as good as the 100 F/2.8 Macro?

No, it wouldn't. The 100/2.8 Macro is significantly sharper.

If you were using it very infrequently as a macro lens this would be a reasonable trade off. It wouldn't be as good as the 100 f2.8 macro which is designed to focus closely, but it would give you that extra stop which is useful for sports and the like.

The biggest downside of the 100 f2 + extension tube is that you will lose your infinity focus while the extension tube is attached. The 100 macro will focus down to 1:1 reproduction and does not require an extension to do accomplish this, so you maintain infinity focus at all times.

If you are planning on doing a lot of macro work, or just don't need the f2 aperture you should choose the 100 f2.8 macro. If you do only the occasional macro shot or really need f2, then the 100 f2 is your lens.

This is an odd question.. if your looking for a macro lens?

So .. get the macro lens.

CyberDyneSystems wrote:
This is an odd question.. if your looking for a macro lens?

So .. get the macro lens.

Please explain how this is an odd question.

Well, the 100 f/2 isn't a macro lens. You stated you wanted a macro len. Macro lenses are designed to give crisp, flat, correct images throughout their focussing range (down to 1:1 at 150 mm in the case of Canon's 100 f/2.8 macro). Regular lenses, like the 100 f/2 are designed to give clear, crisp images throughout their focussing ranges (down to 3', or about 1:10). They're not going to be at their best beyond that, even though an extension tube will let you focus closer.

Let me give you my experience, having owned the 100mm 2.8 Macro. It's a fantastic lens, an incredibly sharp lens, but it hunts around a lot for focus, and it only a marginal 100mm telephoto lens. If you already have a zoom lens that covers the 100mm range, you'll rarely find yourself using this lens UNLESS you are shooting Macro, and then it's unmatched for the price. If you need a prime to cover this range because you have nothing else that will, then go with the 2.0. It will be more flexible, slightly faster from what I've heard (focus speed) and shouldn't hunt around as much.

If you want to shoot bees, flowers, bugs and the like up close, there's no reason to consider the 100mm 2.0 at all.

Adam

oh, and I hate to reply to my reply, but I thought I'd add that my 100mm macro was gathering dust in my bag, since I use the Tamron in the rare case I need to get semi-close to something (it actually does a nice job, although it's no 100mm macro) and I have the 100-400 for long stuff, so the 100mm macro was almost a novelty for me. I sold it on eBay and PayPal'd that money over the B&H for a new 550EX and some other goodies that get used FAR more than the lens did. No regrets, even though for what it does, the 100mm Macro is just awesome.

Adam