Thinking of buying Sigma?

I tried a Sigma 30 and was horribly disappointed. I have resorted to buying only Canon lenses, no matter what. If Canon doesn't make it, I don't need it.

JeffreyG wrote in post #6544019
People can slice and dice this however they want, but there are some unavoidable conclusions that do not need parsing of the data.

In heavy use, the Sigma lenses need service at a much higher rate than the Canon lenses.

In heavy use, the EF-S (non-L) lenses need service at a higher rate than the Canon L series lenses.

The large number of lenses that Lensrentals owns of each type makes the conclusions valid (these are not just one or two lemons).

The heavy use that these lenses see accelerates the failure rate (i.e. Lensrentals probably sees as many failures in 1 year as a more moderate user might see in 10) but this does not change the relative rates.

Can an individual own one of the worst lenses in the list and have a good experience? Of course! This is why anecdotal evidence of individuals is useless for reliability data and a collection such as Lensrentals posted is invaluable.

But, my point is the LenRentals.com comments do not indicate WHY/WHEN/HOW these lenses are failing. Nor do they indicate the failures are due to "heavy use". In fact they actually seem to indicate the biggest frustration is the lenses do not pass OTB inspection rather than failure in use as the biggest issue. For example failure to pass OTB inspection might be a spec of dust on the inside of the element which, for many cases, may not affect real world use...it's still a defect but not as significant as a bad AF or OS or...????

That is all I am saying about needing more exact details.

this is more of the sort of info I was hoping to see:

http://www.lensrentals​.com …09.20/lens-repair-data-10

brecklundin wrote in post #6544223
But, my point is the LenRentals.com comments do not indicate WHY/WHEN/HOW these lenses are failing. Nor do they indicate the failures are due to "heavy use". In fact they actually seem to indicate the biggest frustration is the lenses do not pass OTB inspection rather than failure in use as the biggest issue.

The text indicates that only two of the Sigma lenses specifically were noted for especially needing service as received. It's reasonable to assume the rest (120-300 and 30/1.4) as well as the Canon glass has a more uniform performance over time.

This is literally begging the data to state something it does not. If Lensrentals only problem with the as new parts was some tiny cosmetic defect one would expect that they would mention it. You are wanting to dismiss the entire body of evidence because they didn't clearly state that the Sigma poor performance is not due to a cosmetic defect that most people would overlook?

I'm tempted to cite Occam's Razor here.

entia non sunt multiplicanda praeter necessitatem

aka:
when multiple competing theories are equal in other respects, the principle recommends selecting the theory that introduces the fewest assumptions and postulates the fewest entities

brecklundin wrote in post #6544267
this is more of the sort of info I was hoping to see:

http://www.lensrentals​.com …09.20/lens-repair-data-10

To be honest, I thought that page was what we were already all discussing???

There have been a couple threads on this topic, and the 1st I saw had both the "Sigma saga' link posted in this thread and the data set you just also linked. All of my comments were asuming everyone had seen the data page too....'cause I had!

See we were on the same page afterall... I just hadn't seen that page yet...it's good detail and a great start to really useful info.

JeffreyG wrote in post #6544346
To be honest, I thought that page was what we were already all discussing

'Sigma 30 f1.4 - 14.29% - calibration' So, I guess the sky wasn't falling after all?

Chez Wimpy wrote in post #6545929
'Sigma 30 f1.4 - 14.29% - calibration' So, I guess the sky wasn't falling after all?

Notably, the 30/1.4 has been less troublesome than the EF-S 17-55, and only slightly worse than the EF 50/1.2L.

I do see broad trends that the problems people report here at POTN also track with the chart. The 50L and Sigma show calibration problems, the 17-55 IS unit goes wonky and the 10-22 can come apart in the middle. I've seen threads on all of this here.

Astroturfers anyone?

I'm not sure whether anyone has noticed this, but Sigma is about the only third party lens maker whos lineup eats directly into C&N's lens lineup. Enough people buy the new 50 instead of Canon's 50s, and Sigma's 30 has surely be chosen by many instead of Canon's wide angles. And the 120-400 and the 150-500 has definitely eaten into the 100-400L sales, in fact I haven't seen the 100-400L in shop windows in a while while the 120-400 can be seen in most camera shops - pro and hobbyist.

Lensrentals may really have a problem, but they might have just gotten a bundle of marketing money or a really good deal from Canon. This is definitely not the first public statement of a reputed company where one vendor gets completely slammed while another vendor gats hailed as the only reasonable solution for all problems.

If you look at the numbers: Bigma supposed to have 33% failure rate every year??? This certainly doesn't fit well will what I read in forums like this one. And yes, supposedly the Bigma is used as wild life lens by many, so a 33% annual failure rate would not go unnoticed here, even if these failures occur only in rough environments.

It is clear that Canon has a marketing problem right now, their new cameras and lenses earn yawns while Sigma and Nikon make head lines. It is also clear that Sigma has a QA problem (mostly AF problems), but the lensrentals.com articles sound more like a concerted marketing campain than credible information to me.

Rudeofus wrote in post #6545948
Astroturfers anyone?

I'm not sure whether anyone has noticed this, but Sigma is about the only third party lens maker whos lineup eats directly into C&N's lens lineup. Enough people buy the new 50 instead of Canon's 50s, and Sigma's 30 has surely be chosen by many instead of Canon's wide angles. And the 120-400 and the 150-500 has definitely eaten into the 100-400L sales, in fact I haven't seen the 100-400L in shop windows in a while while the 120-400 can be seen in most camera shops - pro and hobbyist.

Lensrentals may really have a problem, but they might have just gotten a bundle of marketing money or a really good deal from Canon. This is definitely not the first public statement of a reputed company where one vendor gets completely slammed while another vendor gats hailed as the only reasonable solution for all problems.

If you look at the numbers: Bigma supposed to have 33% failure rate every year??? This certainly doesn't fit well will what I read in forums like this one. And yes, supposedly the Bigma is used as wild life lens by many, so a 33% annual failure rate would not go unnoticed here, even if these failures occur only in rough environments.

It is clear that Canon has a marketing problem right now, their new cameras and lenses earn yawns while Sigma and Nikon make head lines. It is also clear that Sigma has a QA problem (mostly AF problems), but the lensrentals.com articles sound more like a concerted marketing campain than credible information to me.

Wow. How so? Or is this just a sneaking suspicion?

runninmann wrote in post #6546159
Wow. How so? Or is this just a sneaking suspicion?

Maybe I'm an old grumpy guy, but I start to see these articles which sound just too good (for certain vendors) to be true. Here's what I noticed in the lensrentals.com page:

• lensrentals.com don't list how many times the respective lenses were rented out, just the total rate of failures. If you want to quantify reliability of a lens, you'd like to know how many failures/use you can expect. If you just want to create outrageous numbers against one vendor, you'd publish what lensrentals.com published.
  
• lensrentals.com acknowledges, that they "seem to be the most aggressive rental house in terms of having lenses repaired or calibrated". Unfortunately they do not provide details what their specific requirements are, only that Sigma seems to fail them hard and frequently. Since the worst Sigma performers don't seem to suffer from the dreaded poor AF performance, but seem to suffer from hardware failure (Zoom mechanism, autofocus, OS), there isn't much where you could be particularly aggressive about, if it's broken, it's broken, period. Unless lensrentals.com declares things as broken which aren't by generall definition. We'll never know. Fact is you'd certainly read it here in the forums if lenses like the 100-300 F/4 or the 120-300 had high failure rates but you don't.
  
• lensrentals.com writes: "We will not stock Sigma when there are better alternatives (70-200 f2.8, 24-70 f2.8", which indicates a measure to be taken in future due to continuous problems in the past. However, both these lenses do not show up in their list of frequently failing lenses

Shrug. I have used many Sigma lenses and have had zero problems with any of them. I wouldn't hesitate to buy one again.

Rudeofus wrote in post #6546587

• lensrentals.com don't list how many times the respective lenses were rented out, just the total rate of failures. If you want to quantify reliability of a lens, you'd like to know how many failures/use you can expect. If you just want to create outrageous numbers against one vendor, you'd publish what lensrentals.com published.
  
• lensrentals.com acknowledges, that they "seem to be the most aggressive rental house in terms of having lenses repaired or calibrated". Unfortunately they do not provide details what their specific requirements are, only that Sigma seems to fail them hard and frequently. Since the worst Sigma performers don't seem to suffer from the dreaded poor AF performance, but seem to suffer from hardware failure (Zoom mechanism, autofocus, OS), there isn't much where you could be particularly aggressive about, if it's broken, it's broken, period. Unless lensrentals.com declares things as broken which aren't by generall definition. We'll never know. Fact is you'd certainly read it here in the forums if lenses like the 100-300 F/4 or the 120-300 had high failure rates but you don't.
  
• lensrentals.com writes: "We will not stock Sigma when there are better alternatives (70-200 f2.8, 24-70 f2.8", which indicates a measure to be taken in future due to continuous problems in the past. However, both these lenses do not show up in their list of frequently failing lenses

Even without the specific info you/we would like it's not difficult to catch the general drift from lensrentals.com. They use a lot of lenses and to take the position they have along with publishing what they have I, at least, give a good deal of weight to it. I have noticed that those that have had bad experiences with Sigma seem to mention it once or twice. They don't get up on a soapbox and repeat their position over and over as do the many that defend a position (in this case, Sigma lenses). Reading the good and bad from a number of sources and reviews one can get at least a general drift. Would I ever buy a Sigma lens? I can't see that happening anytime in the future. Would I ever buy a third party len? Sure, and I hope to when Zeiss' new 21mm f/2.8 in EF mount hits the market. I also would, if I were in the market for, consider a Metz flash along with the Canon. But I would not consider a Sigma flash because of what I consider poor build quality (yes, I have seen and held them) and a number of poor preformance reports that I do not see reguarding Canon or Metz flashes.

jr_senator wrote in post #6547436
Even without the specific info you/we would like it's not difficult to catch the general drift from lensrentals.com. They use a lot of lenses and to take the position they have along with publishing what they have I, at least, give a good deal of weight to it.

Sorry for debunking an obviously biased study published as "research"

I wouldn't be surprized in the least if an independent study comes to the conclusion that Sigma's QA is inferior to Canon's, the price of Sigma lenses supports this.

The so called research published by lensrentals.com, however, doesn't read like an unbiased study, it sounds like a marketing publication, and I suggest we all read it as such. Just look at the outrageous numbers they post.

jr_senator wrote in post #6547436
I have noticed that those that have had bad experiences with Sigma seem to mention it once or twice. They don't get up on a soapbox and repeat their position over and over as do the many that defend a position (in this case, Sigma lenses).

I have no personal interest in Sigma or in defending that company, and certainly don't feel like I'm on a soap box praising them (and definitely not over and over, I may politely point out). What made me suspicious is the lensrental.com article which essentially suggests that anyone picking a Sigma product must be an ignorant fool who hates his money, together with several posters here who fall into this tune.

And before you make fun of people writing three posts defending Sigma: You have 246 individual posts (use forum search to confirm it) in this forum containing the word Sigma (almost all are purely negative about them) although you claim you don't even own any of their glass

And here is a whole WEB PAGE written by someone (in German) who seems to hate them, too.

I understand that not everybody likes Sigma or their products, but the dedication some people put in slamming them is stunning .... or could easily be explained with marketing money

I dont think EVERY lens Sigma produces is a dud. Besides this is info base on lens rentals where the lens is used by several people a year and where people bump, drop and misuse the lens's.