buying used lens, why is date code important?

[pix-shooter]

I don't understand the importance of knowing the date code and serial number on a lens when buying a used lens. (I'm looking at Canon lenses for DSLRs).
Would anyone like to explain it to me, please?

[ngoduyviet]

Date code tells you how old the lens is.

Unless the lens is really really old, in which case Canon no longer service it if it breaks, if it's not too old or abused then it's not really important to me.

[MT Stringer]

Knowing the date it was manufactured will help make you a more informed buyer. It's kinda like buying a used car. Knowing the date it was built, you might realize that 2006 model you've been eying is actually a 1999! :-)
Mike

[Daniel Bates]

You can also often figure out which factory the lens was produced in, if that information strikes your fancy.

[johnastovall]

For one you may want to know if it was early production of a lens which had a recall. The Canon 24-105 was one such lens. You would want to know if the owner had sent it in or you could check the serial number with Canon.

[Truckman]

It's good to record the serial number also, in case of theft or loss (don't ask me how I know)......Ben

[pix-shooter]

Thank you everyone! I appreciate it!
Now that I know that, how do I find out if a specific date code is not a good one to buy, or has had a recall or issues? On the Canon web site somewhere?

[johnastovall]

Just read a bunch of forums and some one will mention it. Also check Canon Supports web page.

[venchka]

I could buy a lens in the morning. Date code yesterday. Trash it in the afternoon.

or

I could buy a lens 10 years ago, take very good care of it, and it would be as good as new.

I have never trashed a lens like the first case. I own 3 lenses that match the second case.

[Marv800]

Originally Posted by venchka

I could buy a lens in the morning. Date code yesterday. Trash it in the afternoon.

or

I could buy a lens 10 years ago, take very good care of it, and it would be as good as new.

I have never trashed a lens like the first case. I own 3 lenses that match the second case.

How do you trash a lens without there being noticable visual or audible damage? Well. I suppose you could submerge it in water and later dry it out :shrug:

[venchka]

I just meant that a date code has no relationship to how the lens had been treated.

[Jim Victory]

Originally Posted by venchka

I just meant that a date code has no relationship to how the lens had been treated.

However all lenses over a period of time, that are used, whether babied or not may need recalibration. This is a possible additional cost in buying a used lens that needs to be considered in the final price.

Older lenses in pristine condition will still sale for less than newer manufactured lenses just because they are older. You just can't tell sometimes by looking at a lens, without testing, if is a good one are not. A newer manufactured lens may have less use on it and therefore less of a need for additonal work like calibration.

If you can't test the used lens your buying then you need to rely on samples by the seller and only deal with sellers whose reputation you can trust.