Sorry to hear that. How did you discover lens was 2nd hand? If there are no scratches at all, what can clue us in that lens is 2nd hand? Can Canon service centre
help?
1. I always request to open the box myself. When I open the box myself, I will open carefully and slowly to observe if there are obvious creases and bends in the box flap.
2. After opening the box, see how is the manual placed inside the box. If the manual is anyhow slotted, and not neatly placed - u know its open.
3. check the Styrofoam that protect the lens to see if the Styrofoam has obvious deep scratches - if yes, most likely its taken out a number of times.
4. check the wrapper that is wrapping the lens - if the wrapper is super creasy i.e. looks like it has been wrapped and unwrapped many many times - most likely the lens has been taken out a number of times. If the wrapper is neat and clean and without much creases, its likely new. (the plastic wrapper that wraps the lens is easily prone to creases, just like plastic bags)
5. check the lens hood wrapper - this is the item that is most easily creased if the hood has been taken out. And then of course check the hood, the hood is much more easier prone to scratches.
6. check the lens itself - the overall lens must look new, no scratches, on barrel, no scratches on surface of lens, and the mounting part must be smooth and shiny and without scratches. check the condition of the black flocking (the black velvet lining at the mounting area of the lens to see if the flocking is smooth and new and not dropping off. Turn the focusing and zoom ring of the lens and see if it feels right. If the lens is those that extend out when zoomed/change focus, check that the extended part of the lens is spanking clean, without much dust/scratches.
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now for the case which I had:
1. the box flap is slightly creased and showed obvious sign of having been opened before.
2. the manual is awkwardly slotted in the box, and not nicely placed.
3. the lens wrapper was very very very creased - like those ntuc plastic bags that have been used numerous times.
4. there are numerous dust on the surface of the lens. I also saw obvious dust particles when viewed from the rear of the lens.
5. at the rear of the lens, the rear black flocking is "dropping" out.
The 5 things I highlighted above were so obvious that my wife which was beside me that day, was similarly able to spot all the same flaws. I immediately rejected the lens.
I was rather sad and disappointed by the store, because I am a frequent patron of the store for years and have trusted them. I never expected the salesperson (whom I knew) to pull such a fast one on me.