A Tale of Two Tamrons (28-75 f2.8's, that is)

I'm on the hunt for another walkaround lens for my 20D, and the Tamron 28-75 f2.8 has caught my eye, however, I've noticed there are two of these on the market, and they're about the same price:

Tamron AF 28-75mm f2.8 XR Di Zoom

and

Tamron SP AF28-75MM F/2.8 XR Di LD Aspherical (IF)

Over on Will Crocket's Shoot Smarter University Web site, they sing the praises of "some" Tamron 28-75 f2.8, but I don't know which one:

"It’s inexpensive and remarkably sharp. Unusually lens flare resistant. We cannot recommend this highly enough. It’s not built in a rough-and-tumble case like Canons ’ version, so it will not hold up to major abuse. But for $900. less, most of us will do just fine with this terrific lens. Price $375. Overal rating: A-"

Anybody know which of these lens is the prefferred one? The second one has more letters, so it must be better, right ?

Dennis
http://www.pbase.com/d​mwierz45/sports_shots

There is only one version: Tamron SP AF28-75MM F/2.8 XR Di LD Aspherical (IF)

I have it love it, and that is what the box says.

I have it and love it use it 90% of the time.

I have it and love it as well. The two versions you have listed are the same, but Tamron has such a long name for this lens that it often gets shortened by the retailers.

What does the "IF" stand for? Can't be internal focusing, because that ring spins like mad when it focuses.

The code of the good one is "A09", this can avoid confusion.

Tamron has a similar one in 28-105, it gives an extra 30mm reach. Is this 28-105 equally good?

Remarkably good lense for the price. On my 20D probably 90% of the time.

Could you explain what you mean by the code of a good one is "A09"? I just ordered mine today from B&H.

They said code of "the good one", meaning the better of their two.

You should be fine, but when you get the lens look at the barrel and find the serail number. A09 should preceed the serial number.

IF = lens elements focuses internally, it has nothing to do with the actual focus ring. In general it means the front lens element will not rotate or extend during focusing.

Mine should be here on Wednesday along with a 20D. Decided to just do it all at once. Can't wait!

Mitch

What is this A09 code number stuff? As far as I know there's only ONE type and that's it. Someone correct me if I'm wrong here?