I thought it might be useful to compile a list of errors or bad technical data listed on the Canon USA website. People here who use the site to obtain technical and pre-sales information would do well to check this list first to see if they're getting the right info in the first place.
Here's what I know about off the top of my head:
1. 17-40 f/4.0 L: The Canon USA website has incorrect MTF charts listed. The Canon Japan website has the correct MTF charts listed for this lens.
2. 100 f/2.8 Macro USM: The Canon USA website has the wrong MTF chart listed. The Canon Japan website has the correct MTF chart listed for this lens. (This is especially problematic for folks trying to decide whether to get the new EF-S 60 Macro or the 100/2.8; one might be led to believe the 60 is significantly better, when in reality they're nearly identical according to the Japanese MTF charts.)
3. The EF lens specification chart pdf that can be downloaded from the Canon USA website has specifications for the various 70-200 telephoto lenses mixed up. I can't enumerate all of the errors, but the weights and lengths are definitely mixed up.
On Canon's website, their lens chart lists this lens as: EF 400mm f/4L DO IS USM
This "DO" lens is pretty much the same build quality as the "L" series lenses, but it's not technically an "L" lens. It's not listed anywhere else in Canon's material with an "L" designation.
I once tried to do a complete google search for all MTF charts on the US and Japan sites and I couldn't find any differences. Can you provide a link to the ones that are wrong? I must have missed them. The thing that most annoyed me was some MTF charts are completely missing. I wonder if that was a mistake or are they trying to hide something?
Thanks for pointing this out Russ. I'd contemplated the 180mm macro due to the much better MTF chart on the USA website compared to the 100mm, but I can see from the Japanese site now that the difference is not that great.
It also explains why I thought my 24-70 was such a poor copy in comparison to my 17-40. I remember now reading before that the USA chart for the 17-40 was incorrect, but had forgotten. The relative performance of my copies of the two lenses matches much better with what's on the Japanese site.
The USA site is pretty poorly RE-designed too and there are many other misleading errors. At the bottom of the each lens / flash page, the icons for the technologies (IS, USM, UD, etc) are incorrect for almost every other page. E.g. why on earth does a 550EX flash unit have 2 UD elements? http://consumer.usa.canon.com/ir/controller?act=ModelDetailAct&fcategoryid=141&modelid=7270
