Lies, Damned Lies, and Statistics

Scott_Quier

Understanding that there are lies, damned lies, and statistics - I thought the following two pages might be of interest. Especially to those who support Sigma and/or are interested in buying Sigma lenses.

http://www.lensrentals.com/news/2008.09.20/lens-repair-data-10

http://www.lensrentals.com/news/2008.09.12/the-sigma-saga

One would be very hard pressed to translate the above data into something useful for purchase decision purposes, but it does make for interesting reading....

Nikolai

Scott_Quier wrote:

Understanding that there are lies, damned lies, and statistics - I thought the following two pages might be of interest. Especially to those who support Sigma and/or are interested in buying Sigma lenses.

http://www.lensrentals.com/news/2008.09.20/lens-repair-data-10

http://www.lensrentals.com/news/2008.09.12/the-sigma-saga

One would be very hard pressed to translate the above data into something useful for purchase decision purposes, but it does make for interesting reading....

Very cool info, Scott, thanks for sharing!
I wonder if our friend BorrowLenses can share simliar stats

RogersDA

We aren’t going to stop renting Sigma entirely but we are going to close out two lines (the 150-500 and 120-400) that have developed so many problems as to be unusable. We will not stock Sigma when there are better alternatives (70-200 f2.8, 24-70 f2.8 for example). We will continue to carry those Sigma lenses that are unique and where there aren’t more reliable options (120-300 f2.8 for example)

We’ll monitor the situation and hope that someday soon Sigma gets their quality control back to “below average” from its current “worse than imaginable” and we can stock them like the other lenses in our lineup.

Those two items seem somewhat diametrically opposed - you can't really stop renting Sigma products and also monitor their damage causes and repair rates (unless other companies are sharing their repair information). Either way I agree with Nik - it's good information.

swintonphoto

We should be careful to not put a blanket statement over Sigma in terms of quality. I know many people who have had extensive use of Sigma lenses without breakage problems. Art Scott for one would stand by that.
So, I think it could be easy because of this to think Sigmas are not good quality, but, for the price, my experience has been that they are more well built than equivalent lenses in similar price brackets. Seems to me this report focuses on two of their lenses that have problems. I know of one Canon L lens that will remain nameless that is extremely popular that has a long history of auto-focus problems, but that doesn't mean we should discredit Canon's great L lenses.

Nikolai

swintonphoto wrote:

We should be careful to not put a blanket statement over Sigma in terms of quality. I know many people who have had extensive use of Sigma lenses without breakage problems. Art Scott for one would stand by that.
So, I think it could be easy because of this to think Sigmas are not good quality, but, for the price, my experience has been that they are more well built than equivalent lenses in similar price brackets. Seems to me this report focuses on two of their lenses that have problems. I know of one Canon L lens that will remain nameless that is extremely popular that has a long history of auto-focus problems, but that doesn't mean we should discredit Canon's great L lenses.

Hence the the OP title.

Tee Why

Interesting,
I personally haven't had any issues with any of my lenses I've bought over the years, 20 or so I'd guess, ranging from Canon, Sigma, Tamron, Tokina, and a lensbaby.

Only the Tokina 11-16mm f2.8 (tow copies) have had backfocus issues (identical 2cm backfocus at 16mm at MFD at f2.8). Otherwise no other issue with any other lenses. Perhaps Sigmas are not built as durable to handle the rigors of shipping as well as the others.

theNOIZ

Rental Repairs

Scott_Quier wrote:

Understanding that there are lies, damned lies, and statistics - I thought the following two pages might be of interest. Especially to those who support Sigma and/or are interested in buying Sigma lenses.

http://www.lensrentals.com/news/2008.09.20/lens-repair-data-10

http://www.lensrentals.com/news/2008.09.12/the-sigma-saga

One would be very hard pressed to translate the above data into something useful for purchase decision purposes, but it does make for interesting reading....

I don't think the information is a good guideline for purchasing a new lens from a company. However, I think it does make you think twice before buying a previously rented lens or a used lens on eBay.

Scott_Quier

swintonphoto wrote:

We should be careful to not put a blanket statement over Sigma in terms of quality. I know many people who have had extensive use of Sigma lenses without breakage problems. Art Scott for one would stand by that.
So, I think it could be easy because of this to think Sigmas are not good quality, but, for the price, my experience has been that they are more well built than equivalent lenses in similar price brackets. Seems to me this report focuses on two of their lenses that have problems. I know of one Canon L lens that will remain nameless that is extremely popular that has a long history of auto-focus problems, but that doesn't mean we should discredit Canon's great L lenses.

- I thought I was being very careful not to throw aspersions on Sigma lenses. If you have any additional doubts about my intent, please re-read my OP. I offered up the two links primarily for entertainment purposes.

There are many people who have had great success with Sigma lenses, Art Scott being among them.

ziggy53

Scott_Quier wrote:

...

There are many people who have had great success with Sigma lenses, Art Scott being among them.

I have 4 Sigma lenses that I am rather fond of, even tho 2 of them don't work properly on modern digital cameras. I still am not ready to sell any of them and they have not failed.

The ones that work really well:

Sigma 18-50mm, f2.8 DC EX (not the Macro version)
Sigma 10-20mm, f/4-5.6 EX DC HSM

The ones that were designed for older film cameras and don't work properly for digital, but I still won't give up:

Sigma 28mm, f1.8 (58mm filter)
Sigma 70-210mm, f2.8 APO (77mm filter)

I use the last 2 lenses as special purpose lenses but they are extremely sharp even wide open and also extremely well-built.

BigAl

As a "I only use Sigma" photographer, I find the second article quite funny, especially vague statements like

Several more broke during their first and second rentals. New copies of other Sigma lenses showed up with high defective rates out of the box.

...and then

We will continue to carry those Sigma lenses that are unique and where there aren’t more reliable options (120-300 f2.8 for example),

where the 120-300 is the lens with the highest failure rate according to their own statistics. Doesn't make business sense to me.

Sensationalism??

jonh68

where the 120-300 is the lens with the highest failure rate according to their own statistics. Doesn't make business sense to me.

Something not quite right. I have the 120-300 and I discovered right off the bat Sigma could do itself a favor and expand the instruction pamphlet that comes with the lens.

1. Straight out of the box, the AF was non-existent. I had to twist the focus ring back and forth several times to loosen it up. It wasn't until after a breaking in period did the AF start to work as advertised.

2. There is a "LIMIT" switch. If you twist the hood, this becomes a limiting switch. I thought my copy was defective as it wouldn't focus past 100yds. One day it was focusing fine and then next it was limited. After playing around with it, I noticed the hood and the end of the glass were twisting around like a focus ring. Tightened it up and it was working fine.

3 Heat: AF will not work if the lens heats up. I was shooting a jet ski competition on the beach in 95+ heat on a sunny day. The lens was hot to the touch. The black coating was absorbing the heat. AF started to become slow to non-working. After cooling it off in the shade, it worked fine.

I think Sigma would do well to document these quirks better and have more than a pamphlet as an instruction manual. With rental lenses probably being used in harsh environments and being used by photographers who don't know the little quirks, I can see how this lens could get a high rating like that. Like I said, I was ready to return it as being defective.

I am now quite happy with the lens so far. I would love to get a Nikon 300 VR 2.8, but I wouldn't get rid of this lens as I like the versatility for sports and wildlife with the extenders.

rpcrowe

Ziggy, I also have a 28mm f/1.8 Sigma

ziggy53 wrote:

I have 4 Sigma lenses that I am rather fond of, even tho 2 of them don't work properly on modern digital cameras. I still am not ready to sell any of them and they have not failed.

The ones that were designed for older film cameras and don't work properly for digital, but I still won't give up:

Sigma 28mm, f1.8 (58mm filter)
Sigma 70-210mm, f2.8 APO (77mm filter)

I use the last 2 lenses as special purpose lenses but they are extremely sharp even wide open and also extremely well-built.

My 28mm f/1.8 will work with my 10D and with my D60 (adapted for full-time IR use) but, will not work with my newer Canon DSLR cameras 30D and 40D.

I agree with you that this 28mm f/1.8 is a very nice lens when it works on a camera and mourn that since Sigma reissued the lens in a new model, they will not or cannot rechip this lens to keep up with Canon technology. It was a great combination with the Canon 50mm f/1.8 Mark-I for low light shooting.

However, my take on this situation is opposite to yours. This is the first AND LAST Sigma that I will ever own. IMO buying Sigma is entering a lottery to bet that Sigma will not discontinue a lens before you will want to use that lens on a newly issued Canon camera.

By the way, I have a Tamron 90mm Macro and a 400mm Tokina, both of which were issued long ago by their respective companies. Both of these lenses also work perfectly with all of my Canon cameras from the D60 right up to the 40D.

Sigma's are nice lenses but, not nice enough for me to enter the "Sigma Obsolescence Lottery" again.

angevin1

Scott_Quier wrote:

Understanding that there are lies, damned lies, and statistics - I thought the following two pages might be of interest. Especially to those who support Sigma and/or are interested in buying Sigma lenses.

http://www.lensrentals.com/news/2008.09.20/lens-repair-data-10

http://www.lensrentals.com/news/2008.09.12/the-sigma-saga

One would be very hard pressed to translate the above data into something useful for purchase decision purposes, but it does make for interesting reading....

Nice find Scott. SInce n=x here, one would say thank god its not statistics!