What to look for when buying a used lens in person...?

[cayenne]

Ok, I've decided to go try maybe the 70-40MM f/4 lens I posted about earlier.

I'm supposed to meet him and examine the lens tomorrow (Sunday) and if it looks good....buy it for $500.

As you might guess...I'm a 100% noob. I got my first DSLR (5D3) last month.

I've never bought a used lens before...so, what should I look for when examining the lens? What kinds of questions should I ask?  As I understand it..this person bought the lens from someone else, so it is at least a 3rd party buy here.

I'm guessing to look carefully at the rear element for scratches? How much is too much? Front lens?

I'm bringing my camera to hook it up..and see how it works, but as a noob, aside from taking some shots to see if AF works....what else should I look for? I'm meeting in a public place....I figure smart for a high dollar item and cash transaction....etc.

Anyway...thoughts on buying a used lens from someone in person?

Thanks in advance, I truly appreciate all the input and advice I've gotten here so far...

cayenne

[Radiating]

Ok, I've decided to go try maybe the 70-40MM f/4 lens I posted about earlier.

I'm supposed to meet him and examine the lens tomorrow (Sunday) and if it looks good....buy it for $500.

As you might guess...I'm a 100% noob. I got my first DSLR (5D3) last month.

I've never bought a used lens before...so, what should I look for when examining the lens? What kinds of questions should I ask?  As I understand it..this person bought the lens from someone else, so it is at least a 3rd party buy here.

I'm guessing to look carefully at the rear element for scratches? How much is too much? Front lens?

I'm bringing my camera to hook it up..and see how it works, but as a noob, aside from taking some shots to see if AF works....what else should I look for? I'm meeting in a public place....I figure smart for a high dollar item and cash transaction....etc.

Anyway...thoughts on buying a used lens from someone in person?

Thanks in advance, I truly appreciate all the input and advice I've gotten here so far...

cayenne

Canon stuff is generally bullet proof until you start doing physical damage to it, except for their micro motor USMs on older lenses (does not apply to the lens you're looking at).

Pretty much the only thing to worry about is physical damage. Check it for physical damage, especially bumps and dings, if that's good then check the glass. If that's good then all you have to worry about is the AF. Get a tripod, mount the lens on a tripod and then have it focus on a brick wall, wait until it locks focus and beeps if you have beep enabled then go into live view and zoom in and then adjust the manual focus ring to see if it's in focus, if you can get it any sharper the lens has focus issues, if not it's good. Do this at various focal lengths. Make sure to switch out of live view when focusing because the camera uses a different system to focus in live view where it just tries to guess and check the focus instead of phase detection.

If the AF and physical condition are good you should have no issues even with a lens 10 years old.

Hope that helps.

[neuroanatomist]

Meet outdoors in daytime - better conditions especially for a slower lens.  Test AF, shoot sky and see that vignetting looks symmetrical, shoot something flat with detail across the frame and check that the corners are similar (equally sharp or less sharp). Check the zoom and focus rings move smoothly.

[cayenne]

Meet outdoors in daytime - better conditions especially for a slower lens.  Test AF, shoot sky and see that vignetting looks symmetrical, shoot something flat with detail across the frame and check that the corners are similar (equally sharp or less sharp). Check the zoom and focus rings move smoothly.

Thank you one and all...making notes for when I meet tomorrow afternoon.....

Please, if anyone has further suggestions...keep posting them!

C

[bkorcel]

Look for signs that it may have been dropped.  Check the filter ring for dents.  Examine the glass.  Should be clear with no haze or spotting.  Check the external surfaces for scratches or fungus spots.  Small stuff on the front glass may be ok like dust speck sized spots but not too many.  Make sure any manual focus rings or zoom rings operate smoothly and dont bind anywhere in the full cycle of the ring. Electronically, make sure the AF will switch quickly from it's closest focus to infinity and back....do that several times in a row.  If the lens has IS you need to test the IS capability in landscape and portrait mode (hold the camera with the top facing the left and again facing the right).  IS should function smoothly in all three positions and it should hold firmly without jumping or wiggles.  Take some shots with the aperture wide open..check the sharpness wide open.  Take some shots stopping the lens down each time to F/16 (most people wont shoot smaller than that).  Make sure all images are exposed properly.  Also check the edge of the images for chromatic aberations (where the colors dont seem to line up in the same place) some call it color fringing.  On the wide setting you might see some color fringing at the edges.  There should be none in the center of the image.

All in all Canon lenses are hard to break no matter what you do to them.  The IS systems are somewhat sensitive so you should make sure that works perfectly if the lens has it.  Other things to look for are signs that it might have been in water or if you see ANY and I mean ANY sand particles anywhere.  Sand and salt will kill electronics.  If you see any sand, walk away.

Good luck...If you can try to stick with L lenses with that 5DMIII.  They perform to their full potential with L glass.

[bkorcel]

Are you looking at the Canon EF 17-40mm f/4L USM?  The 70-40 doesnt exist so I assume that is a typo.

[TexPhoto]

1. Visual inspection.
2. Shoot with it on your camera.  make sure it auto focuses,, exposures are correct etc.   Consistantly.
3. Shoot something flat that has detail, like a brick wall.  Examine at 100% for sharpness, check center, and all 4 corners. 
4. As with any purchase online or off, know the going rate.  Don't spend $500 on a $700 retail used lens only to find them new for $480, or used for $350.  eBay completed auctions is a good place to check.

[Marsu42]

no matter what you look for, there is always a factor or 'luck' in buying used.

Other things to look for are signs that it might have been in water or if you see ANY and I mean ANY sand particles anywhere.  Sand and salt will kill electronics.  If you see any sand, walk away.

My 2cents: carefully listen to the usm motor working, if there's any sign of scratching, it might be sand/dust. This was the first early warning sign when my macro lens broke down - in this case, everything works just fine and then suddenly the lens breaks with err01 requiring a $250+ repair.

[MintMark]

As well as all that good advice, you can do an aperture test.

Set the lens to f/16, look into the front element and press the depth of field preview button. You should see the  blades close to form the smaller aperture. Make sure all the blades close and open again quickly as you press and release the button.

   Mark

[cayenne]

Are you looking at the Canon EF 17-40mm f/4L USM?  The 70-40 doesnt exist so I assume that is a typo.

Yes...typo....17-40mm

C

[bdunbar79]

Absolutely some of the best advice given so far is to take your camera with you.  Shoot several shots wide open for sure.  Shoot the sky, walls, contrasty scenes.  Whatever you like.  I'd check each end of the zoom, 17 and 40mm.  There will be differences that are normal.  Midway some zooms show a bit of barrel distortion, but you won't notice.  Physical things have already been stated.  I'd try a shot at like f/11 or f/16 and inspect DOF sharpness.  Are you able to upload your photos onto your computer from your card prior to making a purchasing decision?  I don't see why you couldn't post some on here and have us look at them.

[Mt Spokane Photography]

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.

[bdunbar79]

Right.  But you can test for subtle differences if you import to computer. 

[cayenne]

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!

C

[Axilrod]

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!

C

It sounds like everything went well.  People tend to take care of their gear, especially when it's expensive.  I've bought tons of lenses used and haven't had any issues at all.  The 17-40 is a very solid lens, and unless you shoot in low-light constantly you're not missing much with the 16-35mm.  And as well as the 5D3 does at high ISO's you really don't have much to worry about. 

The 14L is a great lens, very sharp, but it's expensive as hell and not near as versatile as the 16-35 or 17-40.  It's a good lens to have, but it's definitely not anywhere close to one of the first lenses I'd get if I was starting a collection.  It was the last Canon lens I got, there are just more important lenses to get before that one IMO.  Enjoy your 17-40 and try not to get too wrapped up in lens acquisition, the more you buy initially the harder it is to master each one.