Lens Quality variance - what to look for?

[farmer]

I'm looking at buying a Canon  100-400 mm IS USM (either used or new) for a Canon Rebel 2Ti. I've read on this forum ( and elsewhere) that there can be some lenses that vary in quality.
What should I look for to be sure I don't get a "poor" quality one?
Is it a good idea to buy a used one, what can go wrong with this lens?
I love to hear your experience/advice, thanks!

[Michael Tam]

The issue of lens variance is not generally a question with Canon and Nikon line of product, particularly with the higher series such as Canon L series lens.  However, it is surprising to see in the following review that the issue of QC is present:

http://www.photozone.de/canon-eos/204-c ... rt--review

I have purchased two used (or pre-owned!) lenses, a Nikon and Tokina from my trusted professional camera store in the past 20 years, Downtown Camera: http://www.downtowncamera.com/.  Both are flawless since they have been thoroughly examined, as well cleared through the RCMP database to ensure it is not a "hot" item.  Otherwise, one will encounter problem in the future such as border crossings or insurance coverage.  Although it may be not be the cheapest route to find your lens, it is the peace of mind that matters. Hope it is helpful.

Good birding and photography

[farmer]

Thanks, I had not seen that particular article. It did say that there was some good samples and some that were not quite as good. However I still think I'd be better off, to get the Canon 100-400 mm rather than a Sigma 150-500mm (even though it is cheaper). Does anyone agree/ disagree with this thinking?

[Michael Tam]

There was a thread in this forum titled "Info on a Lens" recently with extensive discussion between the choice of Canon 100-400 vs Sigma 150-500 lenses.  In general, there were more threads concerning lens variance ("a good copy") on the Sigma products in the past.

There is one further consideration within the Canon line for your decision:

http://www.photozone.de/canon-eos/173-c ... rt--review

Good birding and photography.

[farmer]

Thanks for your help Micheal, I picked up a used Canon 100- 400 mm yesterday, and love it so far! Was out for a couple hours today.

[Michael Tam]

This article I came across describing in detail, well may be more than enough detail  :lol: , about lens testing.  Please read the article below:

http://www.normankoren.com/Tutorials/MTF5.html

Good birding and photography

[Michael Tam]

For those who absolutely need to know the quality of their equipment, please read the following comprehensive article   :lol: on the subject:

http://www.imatest.com/docs/lens_testing.html

Good birding and photography