Its absolutely impossible to test a lens mounted to a camera for subtle issues like sharpness or decentering, you can verify te AF works, Iris stops down, manual focus and zoom rings work smoothly, and that the glass is clean and clear, and general condition.
I also evaluate the seller. Does the seller appear to be knowledgable about the lens, why is he selling it. If the seller does nor know anything about it, thats a red flag. You can often, but not always tell if a seller is lying. Do they have the original receipt, etc.
Thank you one and all for the great primer on evaluating the lens.
It is VERY rainy out here in the New Orleans area today...met in a coffee shop to evaluate the lens.
Nice young kid, seemed to be interested in photography...big hobby of his. He's wanting to sell some zooms like this one and move into primes.
Seemed a nice kid.
Front and rear elements on the lens looked nice....motor seemed to move from infinity and back quickly...no discernible noise. Body of lens was in good shape...no scratches or anything. ONly thing really that showed any dings or wear, was the hood itself, and I'm ok with that.
He didn't have the pouch that goes with it....and he forgot to bring the UV filter he had for it...said when he gets back on this side of the lake again, he'd try to remember to bring it and holler at me to meet him for it.
Anyway, I think I'm very happy with my purchase.
As per the other thread, this is the 17-40mm f/4 L. I got it for $500 even.
I had been wanting to save a bit more and get the faster 16-35....but I think I got a good deal on this one, and this will give me wide angle to play with for awhile. I might even look into keeping this one, and saving for the 14mm to get something faster and even wider.
Anyway, from my research and feedback on this forum (thanks guys!!) this looks like a good deal, and likely as not, if I find I want to...I should be at least able to get my money out of the lens if I wish to resell it.
LOL...I'm guessing some of the tables of girls in the coffee shop were getting a little self conscious with me shooting all kinds of pics of them with my big camera, etc....gotta go back through and look at the images to see if any keepers...
Thanks to all!