I've got the older 170-500 and it is a nice lens. Draw back for me would be the short side, 170mm. Quite a bit if your're to close the the subject. Just looked up the D60 in a catalog and it's got plenty of resolution to crop a photo. More than my D5000 and I can crop a lot with it. I think I'd go the 70-300 route also. For shooting dog's I use a 55-300 Nikon. Don't need the 55mm much and probably wouldn't need the 70mm much either but about 135mm works out well. Problem with less is that when the dog get to where I could actually use a wider lens they are going so fast I can't catch up Any way.

I'm going to get one of those Tamron lens one of these days. Had a 75-150 a whole lot of years ago and it was super. Now they don't focus on my D5000 so for now Tamron is out. I do have a Sigma 70-300 and it does alright but, well, I wouldn't buy another. feels cheap.

Last edited by DonFischer; 09/10/13.