I am looking at buying a macro lens to use on my D300, and most likely some use on my new to me FE. From the research I've done I have found as most of you probably know that there are many versions of this lens. I will be using this lens for macro 90% of the time, so I would prefer the version that is more suited for macro and not "corrected" for focusing at distant objects. How can I be sure that I get the earlier version? Make sure it has the dual(compensating) aperture numbers? Also what is an AI'd version? I see one at KEH that has this designation. Is that the earlier version? BTW. Does anyone happen to know if KEH shows the exact model of the lens or just a general picture of the model. I know it's not the actual lens they show a picture of. I know I can call them, I just didn't know if anyone knew for sure.