Sigma 24mm f/1.4 DG HSM Art Coming in October

[mackguyver]

+1 on the 24 L II having AF issues, I had three copies, two Canon took back and agreed sucked and the third was pretty useless, but a bit more stable , worst Canon AF I've used of the 30+ Canon lenses I've owned.

People that are defending useless AF needs to know that I don't buy an AF to use it as a manual lens, I must have AF for the photography I do. What the lens cost matters NOTHING if the AF doesn't work, you can't say it's okay for a lens that price, if it doesn't work then it doesn't work and if it cost 1 dollar I still can't use it. Sigma releases it as a fully compatible lens WITH AF, when it's not it becomes a big problem for everybody.

I guess I've been very fortunate with my 24 II I've used in on many bodies and typically shoot between f/1.4 and f/2 and have never had any issues with it. I agree on AF - if it doesn't work close to 100% of the time, the lens is worthless.

 

[jasonsim]

The Canon EF 50mm f/1.2L USM does not AF very accurately either. I get some misses even on a 1Dx and must sometimes "rack" the AF, before I can trust it.

The AF on the Sigma 35mm f/1.4 Art was really reliable for me on the 1Dx and 6D. So, I would not discount that Sigma has improved things drastically in these new Art lenses.

Kind regards,
Jason

I say Sigmas AF in the new lenses is pretty good for the money....

If I can't trust it, it's worthless.

That was how I felt with the erratic and occasionally brilliant old model Sigma 50mm f/1.4.
My two copies got used for some personal work, endless testing but simply couldn't be trusted for client work. Therefore ultimately worthless.

I truly hope Sigma finds an AF fix for the new lenses deliverable via firmware. The optics are clearly awesome, but without dependable AF they're a commercial no-go.

-pw

 

[CarlMillerPhoto]

The AF on the Sigma 35mm f/1.4 Art was really reliable for me on the 1Dx and 6D. So, I would not discount that Sigma has improved things drastically in these new Art lenses.

I'm not sure why people here are still calling for an AF improvement from Sigma. The new Art series remedied AF issues (AF as good as the average Canon, imo), and the USB dock is there to maintain it into the future. All these complaints seem to reference older Sigma lenses, which were obviously sub-par compared to the new quality standard.

Anyway, I was really hoping 24mm would be their next release, so I'm a very happy camper.

 

[jdramirez]

We have no way of knowing which of the sample 10 photos is most representative of the most optimum focus his particular camera and lens combination is capable of producing.

There are 10 images presented, 6 of which are similarly sharp, 4 of which are not as sharp (and one of those 4 is a blurry mess). Are you suggesting that the 6 similarly sharp images are all random misses from optimum focus that happened to coincide in terms of sharpness? I think Friar William of Occam would disagree with you.

Precision and accuracy are independent, although they may certainly appear to be related, depending on the resolution of the measurement method relative to the accuracy and precision of the system being tested.

I certainly agree that it's premature to base an overall conclusion about the 50A's AF perfromance on issues found by two review sites, each testing one lens.

In this instance of trying to measure precision, the lens could be front or rear focused. So the to and fro of the lens at its furthest point might look like a mess, but if the lens were afma'd correctly, the focus could be within three units of the proper focus... making all of the shots tolerable versus some of the shots being as many as six units of auto focus off.

We want to make sure we are only identifying its precision... not its accuracy which is why afma is a requirement.

 

[that1guyy]

ITT: Canon fanboys threatened by Sigma and prematurely attacking Sigma's lenses. How pathetic.

 

[BLFPhoto]

Exactly. Without a reference point, it's hard to say what shots are more indicative of the specific sample's ability to focus. And the delta could be a clue to some symptom or reason for the lack of consistency.

One thing I didn't note yet was that few details are given of the specific setup of the AF, including all AF-related CF settings. Without that information, interpreting the results effectively is problematic at best.

It could very well be the case that certain configurations of AF, for certain bodies or AF modules, give problematic results for these 3rd party lenses, for the well-noted reason that the AF algorithms are developed from reverse engineering. The issue could be local to that specific configuration and not a global issue, and the lens could therefore otherwise perform admirably. Should we throw out the baby with the bath water in that case?

 

[Loswr]

In this instance of trying to measure precision, the lens could be front or rear focused. So the to and fro of the lens at its furthest point might look like a mess, but if the lens were afma'd correctly, the focus could be within three units of the proper focus... making all of the shots tolerable versus some of the shots being as many as six units of auto focus off.

We want to make sure we are only identifying its precision... not its accuracy which is why afma is a requirement.

We are able to assess precision, and from this one test with one lens, it's very poor. If all 10 shots were made three units sharper, you would still have six equally sharp shots, and four less sharp shots – i.e., the AF would still be inconsistent. The whole point of AFMA is that it's a global adjustment.

Also, be honest…do you really think that Bryan does not AFMA lenses prior to shooting with them and testing autofocus performance?

 

[BLFPhoto]

No. I don't think that. I think there is not enough information to adequately assess the results and pronounce the lens inconsistent as a rule of thumb.

 

[jdramirez]

it has been well over a decade since I have written a scientific paper. but if I recall correctly when you do perform a scientific tests and you write down the results it is incumbent upon you to describe set up as well as the preparation to eliminate and control variable.in this instance there are sufficient questions which can be brought up. much of the same way scientific papers by prestigious and well-respected scientists are peer-reviewed. the assertion that he did or did not used in a can be disputed because he did not specifically site whether she did or not. additionally it would have been helpful, and maybe I missed it , if he listed the lighting conditions in a unit of measurement such as foot candles or whatever other units.

 

[Viggo]

I say it's VERY unlikely that Bryan makes a mistake that big, he KNOWS his stuff better than 98% of us here. Forget that.

Second, Sigma hand picked the lens for him, make no mistake, that lens is not a randomly selected one off the shelves at Sigma. Forget that.

Third, the 35 art has the same issues, some lenses are good and others, like myself had a pi$$poor one. Whic leads me to

Forth, if the AF is consistent with another reviewers 50 art, and another claim it's faster and better than any other, a third says it's poor in low light and Bryan shows you it's HIGHLY inconsistent, then the issue of extreme copy variation is still a fact. Which makes it a lottery to buy and get a good one. I have also read about 35 art's that worked initially, but then started to drift in afma correction.

It's not about bashing Sigma, it's just such a great shame they have FANTASTIC lenses that can't be trusted...

 

[sdsr]

I'm not sure why people here are still calling for an AF improvement from Sigma. The new Art series remedied AF issues (AF as good as the average Canon, imo), and the USB dock is there to maintain it into the future. All these complaints seem to reference older Sigma lenses, which were obviously sub-par compared to the new quality standard.

Sigma's newer lenses may be better, but there are complaints about them too - reviewers and users both complain about focusing inconsistency even though they praise the lens in question to the skies in other respects (e.g. 35mm 1.4 and the 1.8 zoom).

The AF section of Lenstip's review reaches a rather different conclusion from Bryan's: AF accuracy of the 50mm A varies with the camera model - on a 5DIII the fail rate was c. 6-7% (which he describes as good, but not better than that), but far higher on a 1DsIII:

http://www.lenstip.com/400.10-Lens_review-Sigma_A_50_mm_f_1.4_DG_HSM_Autofocus.html

This perhaps shouldn't be surprising, especially given the reverse engineering Sigma is forced to do (remember the Sigma/Nikon D5300 problem?). It's also the case, as Roger Cicala has shown, that some newer Canon lenses focus much more accurately on a 5DIII than on other Canon bodies. As for how consistent Sigma's AF inconsistency is, perhaps Mr Cicala will test that too - no-one else seems to be able and willing to test umpteen copies of the same lens.

(My experience, which is statistically near-worthless, is that of the three Sigma lenses I've owned, and the few I've rented, most of them older, only one gave me AF problems - a copy of the older 50mm 1.4 which seemed to refuse to focus on anything, ever.... Aside from that, my worst focusing lenses were various Pentax lenses and my first Canon 50mm 1.4.)

 

[Loswr]

...it takes two to tango or in this case autofocus (camera plus lens.)

True, but it's hard to dance with a partner that has two left feet, one of which they tried to reverse-engineer to be a right foot.

I would have said that it's hard to dance with a partner and match their footsteps when you can't see their feet

Fine...but Canon owns the dance club and calls the tunes. If Sigma can't keep up or trips over their own feet, that's not Canon's problem.

 

[Viggo]

Second, Sigma hand picked the lens for him, make no mistake, that lens is not a randomly selected one off the shelves at Sigma. Forget that.

And you know what Sigma did because ...?

Because anyone knows that a review over at TDP is the benchmark and have always been serious and accurate with every lens tested, meaning you just make sure to give him a best possible lens because people buy or don't buy according to their findings. And you know as well as I and as well as Sigma, copy variation is a fact, and why would they risk giving him the worst they made? It's no possible they leave that lens to chance. And they still gave him a non working lens, so does that give me high hopes for a retail lens? Nope..

And why do you think he goes out of his to retail buy (almost) every lens tested? And then state it clearly in every review? And equally, states that this lens was provided by Sigma themselves?

 

[jdramirez]

...it takes two to tango or in this case autofocus (camera plus lens.)

True, but it's hard to dance with a partner that has two left feet, one of which they tried to reverse-engineer to be a right foot.

I would have said that it's hard to dance with a partner and match their footsteps when you can't see their feet

Fine...but Canon owns the dance club and calls the tunes. If Sigma can't keep up or trips over their own feet, that's not Canon's problem.

Who dances at the club? Don's you just buy a whiskey sour and lets the girls gyrate up and down?

 

[Solar Eagle]

How quickly "new" Sigma's reputation went downhill. The 35A was hailed a great lens and now a lot of forum members seem to be bashing the 50A before they get their hands on a copy. And now some are already saying that this will have poor autofocus performance. I am quite excited for this lens for night and astro as the Canon 24L has more coma than I would like for star shots.

The key words there are "forum members", and those vocal few who think their complaints change the state of the game represent a very small portion of the market. The gap between what people want and what people get creates suffering for them, and people express pain as anger... I supposed its best to cut the complainers some slack though, since they have it hard enough already... poke poke lol ;-)

As to the lens, this is the Sigma I've been waiting to hear about. I passed on the 35A and bought the 35 IS, and will also be passing on the 50A in order to wait for the 50 IS. If the sharpness wide open and coma are good on the 24A I might actually get it like you say for star shots...

 

[Lee Jay]

The order these f/1.4 primes would interest me is 35, 24, 85, and 50 would be last.

 

[Loswr]

Unless he states that he does or does not, one cannot assume either way => i.e. we don't know.

Whether or not it was done should be mentioned for completeness.

I see. He also didn't state explicitly that the camera was securely clamped into the tripod head, nor did he state that the tripod was not set up on a sandy beach with the tide coming in, nor that his youngest child was not banging on one of the tripod legs with drumsticks during the test.

Here's the thing…those bits of silliness above would have affected the results, but whether or not AFMA was applied would not change the relative sharpness of the shots, and therefore not change the conclusion.

 

[CarlMillerPhoto]

Unless he states that he does or does not, one cannot assume either way => i.e. we don't know.

Whether or not it was done should be mentioned for completeness.

I see. He also didn't state explicitly that the camera was securely clamped into the tripod head, nor did he state that the tripod was not set up on a sandy beach with the tide coming in, nor that his youngest child was not banging on one of the tripod legs with drumsticks during the test.

Here's the thing…those bits of silliness above would have affected the results, but whether or not AFMA was applied would not change the relative sharpness of the shots, and therefore not change the conclusion.

Seriously? An appeal to what's relative? AFMA would have shifted the spectrum of focus variability, perhaps into a more accurate range. Pure and simple. Yes, it would not change the measure of focus variability itself (assuming all other things constant), but it would change focus accuracy and objective (not relative) sharpness. So, don't be juvenile and try to trivialize its mention. I would think you'd endorse disclosure of methodologies, but maybe your background isn't that rigorous.

 

[JumboShrimp]

Just me, but I wish they were releasing a 28/1.4 ART. I have always preferred that focal length over all others.

 

[pwp]

I'm not sure why people here are still calling for an AF improvement from Sigma....

If there were no issues, then conversations like this wouldn't exist.

Most people really want to see Sigma totally bury their past reputation of extreme copy-inconsistency and stabilize to the point where their now optically brilliant lenses can be trusted to deliver. And they're doing this darn quickly.

The way Sigma is currently progressing it probably won't take too long, but right now they're still not quite ready for high-demand commercial prime-time.

Shooting an expensive job/project for a client, you simply cannot risk using even mildly doubtful equipment whether that's a lens, a body, CF card, lighting equipment and even the car you drive to get there. A professional's reputation is only as good as their last job, you have to deliver 110% of the time or risk losing your business. It's cut-throat. So hurry up Sigma. I like where you're headed.

-pw