About to buy a used 17-35mm how can I test it first?

<p>Hello everyone,<br>

I have found a 17-35mm 2.8 on a local community list serve that is said to be in great condition with all original boxes, caps, hood, case and is a USA lens. My question is can anyone suggest a way to test the lens on-site at the person's house to make sure it's a good copy? Are there any red flags other than cosmetics? Aside from a few test pops on my D700 and then zooming in on the lcd (which will tell me next to nothing) I'm at a loss for protecting myself against losing $1200 on a bad copy that back focuses or has some other problem. I guess I have to factor in the human element as well, I'm sure this person doesn't want me at their house for an hour with a laptop and card readers etc.<br>

Any suggestions would be greatly appreciated. Since getting my D700 I'm faced with changing over from all those DX lenses and this is one I could really use and I just can't afford the extra $700 for a new version of the 17-35.<br>

Thanks in advance.<br>

Mike</p>

<p> </p>

<p>Two comments:</p>

<ul>

<li>The main concern for an old 17-35mm/f2.8 AF-S is whether the AF motor is in good shape. If you hear some sharp squeal when it auto focuses, it can be an indication of a problem.</li>

<li>Since Nikon has announced a new 16-35mm/f4 AF-S VR, would you consider that new lens instead? Potentially the new lens may be better optically and if people tend to upgrade to the new lens, value for the old one may drop in the future. Of course, the new lens is an f4 instead of f2.8.</li>

</ul>

<p>A few basics to check with any purchase of a used lens:</p>

<p>Check the condition of the aperture blades to be sure they're free of oil and open and close snappily. Sluggish opening and closing indicates a problem that will require servicing by a tech.</p>

<p>Check the filter ring rim for signs of dents or repaired dents (buggered filter ring threads are a giveaway of amateur repairs). In my opinion, once a lens has been struck hard enough to dent the filter ring rim, it's too risky, at least with a complex zoom. Optical elements can be decentered and it'll be difficult to achieve edge to edge, corner to corner sharpness. Repairing a dinged filter ring rim won't fix the internal alignment problem, it just hides it. However, in some cases a qualified shop can fix alignment problems.</p>

<p>Check for missing screws. Checking for buggered screw slots - another sign of incompetent DIY repair attempts. Good techs will always have a huge supply of screwdriver bits to ensure a perfect fit with slotted or Phillips screws - they'll even custom fit bits to mate perfectly with screws for a particular item. Amateur DIYers will take shortcuts and won't bother making sure the bit and screw are perfectly mated.</p>

<p>Rotate the focus and zoom rings manually throughout their full range. Check for unusual hitches in the rotation. It's not unusual for a complex zoom to have a slightly different feel at some points in the rotation, as some of the inner elements and complex helicals may be swapping directions at some stages. But even then the movement should be relatively smooth, not gritty or balky.</p>

<p>Bring a small flashlight and check through both ends of the lens for haze or fungus - irregular fine, thready patterns. Dust should not be a factor unless it's extreme - all lenses, especially zooms, eventually accumulate some internal dust. But an even coating of haze can impair contrast and cause more flare. Fungus will gradually spread and make the optics useless for any critical photography.</p>

<p>Look for odd rainbow patterns along the edges inside each optical element or group. In some cases this is merely due to the fact that it's very difficult to clean a lens perfectly along the edges where the optics contact the lens barrel - it's just a surface residue. But in some cases it can indicate separation of glued elements. I'm not familiar with the 17-35/2.8 AFS Nikkor optical design and don't recall whether it has any glued elements and haven't heard of any reports of separation, so I wouldn't expect any problems here.</p>

<p>But, again, if you see several dust spots, even a dozen or so, it's not a cause for alarm. All lenses eventually accumulate dust.</p>

<p>Many many Nikon 17-35 afs sqeal. Of all the Nikon AFS lenses I have that one sqeeks.<br>

Actually none of the others sqeek at all. Its just something this lens does. Can be fixed I' sure but mine and many others have sqeeked for years and years with no ill affect. </p>

<p>You could do it this way. Spend 20 minutes at his place taking test shots. Go back home, transfer the pics, pixel peep, and make your conclusions. Then decide if you want to go back and buy it.</p>

<p>I must be lucky. I have two and neither squeaks. I am thinking of putting them on eBay when I get to find and put everything together - the cylinder case, the box, the lens hood (not sure where they are at this point), the manual, etc. I hope the buyer will not go through the above procedures before buying, or it's going to be too much trouble for me. ;)</p>

<p>When I have sold lenses or DSLR bodies I always offer to put up with the potential buyer hanging around for an hour while he/she tests the lens; also I offer to hold the item for a reasonable time if the buyer wants to shoot and analyze the results at home. If the seller believes his/her item to be non-defective, they should allow for testing. </p>

<p>Thanks so much for all the suggestions.....except the one where Shun made me start thinking about holding off for the new 16-35mm f/4. :o) I have been saving for the 17-35 for a few months now and I'm finally there when up pops this new 16-35. What's a guy to do? Everything I read about the 17-35 all this time made it seem like the perfect lens especially since I do a lot of event/PJ stuff. I have the 50 1.8 and the 80-200 2.8 so all I am really missing for FX is that wide end. The 17-35 seems so tried and true whereas the 16-35 may go through some growing pains being so new and all.....thanks again to everyone!</p>

<p>If a 17-35 has been sitting for a long time, it will squeak when the motor turns. Before you even power up the camera, turn the focus ring. If you hear a squeak, it's probably just because it's been sitting. Mine has been doing that for six years. I think Rockwell attributed this to dust.<br>

If it keeps squeaking through use, it might have a failing AF motor. <br>

As with many things Nikon, if you send it in they'll be happy to charge you $350 (or whatever a Class C is now) to replace the motor (need it or not). The good news is that it's a fixed price, and they'll fix whatever else you want at that point. If you get a deal, it may be worth it to send the lens into Nikon, have some preemptive maintenance, and get the 6-month (IIRC) repair warranty.</p>