Are there more problems with non-Canon lenses than with Canon?

The only thing I can add to this thread is that with all my sigma and tamron lenses I seemed to have focusing dificulty. Not problems just difficulties, slow, and more hunting than my canon lenses.

Tamron 28-75 2.8 is as sharp my my 24-70 L but the auto focus was just slow(er) and did a lot more hunting.

Sigma 150mm also did some hunting, but for what I used it for it wasnt an issue. Plus it was very sharp

Bigma 50-500mm did not get a lot of use, but the autofocus was slow as hell. This could be due to the fact that it is a 10x zoom?

condyk wrote in post #2083607
You think people feel more affection for the 3rd party stuff then?

Someone needs a pet.

My vote for best thread of the year.

I know there is no proof or study done to prove anything here but I still say what I originally said. This forum is entirely made up of end users. No one here just writes reviews or has an agenda to promote or bad mouth any brand of photographic equipment and I clearly recognize that what we see here is a small sampling.
I read a lot of posts in all the Canon forums and there is no question that from the sampling here there is definitely more negative commentary about third party lenses, specifically Sigma but Tamron. I understand that no manufacturer or piece of equipment is going to always be 100% and you can always get a bad one right out of the box. You can by a brand new Mercedes and have trouble with it right off the lot. I know this. However, it always jumps out at me when people make mention of a lens hunting to focus or being noisy and I see this type of comment and review quite often. Yes I do see the people that post about there new Sigma lens and it is outstanding and they love it. I am not saying that these lenses are bad or crap of that we should not try or buy them. I've seen bad reviews of Canon lenses as well, just not in the same numbers.

Not trying to start trouble. It was just an observation.

I don't have scientific data on actual failure numbers.

I can tell you this with certainty.:
There are more complaint threads of third party lenses on this forum.

However this is colored by so many variables, not the least of which was the RASH of error99 issues with the release of the 10D (if you weren't around don't ask, but frankly I can't blame the 3rd parties for this issue, it just happened)

Now with that out of the way, what ever marginal "lead" that 3rd party complaints has over Canon lenses could easily explained by the number of units being purchased in a given price range. Combining all third party lenses in a lump to compare to Canon, clearly the numbers are not going to match for how many are purcahsed.

ie: I'd say no reliable conclusion can be drawn from what we see on forums. Even if we compiled all the numbers into workable data. (anyone want to try that ? )

TMR Design wrote in post #2084600
... there is no question that from the sampling here there is definitely more negative commentary about third party lenses, specifically Sigma but Tamron.

I won't argue your claim, but this is ppart of what I'm saying above,. there are FAR FAR more Sigma lenses being purchased by members of this forum than Tamron. With the exception of the 28-75mm, Tamron has no really popular lenses here, where as Sigma has several. Again no actual data to show, but there is no question based on discussions, polls, threads, etc that POTN members buy more Sigma lenses than Tamron,. the difference is probably on several orders of magnitude.

Thus, if we as a whole purchase 5 times as many Sigma lenses vs. Tamron, than it is reasonable understand that we as a whole might post 5x as many complaint threads about Sigma.

CyberDyneSystems wrote in post #2084695
I won't argue your claim, but this is ppart of what I'm saying above,. there are FAR FAR more Sigma lenses being purchased by members of this forum than Tamron. With the exception of the 28-75mm, Tamron has no really popular lenses here, where as Sigma has several. Again no actual data to show, but there is no question based on discussions, polls, threads, etc that POTN members buy more Sigma lenses than Tamron,. the difference is probably on several orders of magnitude.

Thus, if we as a whole purchase 5 times as many Sigma lenses vs. Tamron, than it is reasonable understand that we as a whole might post 5x as many complaint threads about Sigma.

Point taken.

I have enjoyed this thread because it has given me a lot to think about. I may just go to Penn Camera next week and try out the new Tamron and Sigmas out. I was ready reviews in photo magazines for about a month now and some of the new offerings are impressive. I was actually surprised that Canon came out with only a few items at the Photo thing in Germany. I have owned Sigmas and Tamrons off and on over the last 15 years and I have to say, I haven't given them a far shake. I usually go straight to the Canons if I have the funds. This thread has me thinking I can't judge what I don't know for sure. Even then, a lens or camera only does what the human tries to do with it. No such thing as camera equipment miracles.

Good posts CDS. Stuff I think people really need to take to heart. There's WAY WAY more positive posts for all manufactures, Canon, Tamron, Sigma, Tokina etc. then there are negative posts. Companies couldn't stay in business if they were as bad as the internet made them to be.
In all actuality, I'm a Canon fanboy. But Sigma makes lenses in my budget that work really really well. Even if I could afford the Canon counterparts for some of them, I don't think I'd buy them.