April 23, 2014, 12:28:24 PM

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Messages - Rudeofus

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Having said that, the design age of the 50/1.8 II and 50/1.4 certainly don't seem to bother the buyers on Amazon.com, where the Canon 50/1.8 II is the #1 selling lens and the Canon 50/1.4 is the #3 selling lens.  You need to go to #36 on their Top 100 list to find the first Sigma lens, and the Sigma 35mm f/1.4 Art isn't on the list at all.


That list contains quite a few oddities which makes me wonder how accurate it is:
  • The 24-105 L IS is listed twice, once at rank 13, then again at rank 25. Given that it comes as kit lens to many ff cameras, I wonder how many people buy it later on. In the used market it is sold at fire sale prices ...
  • Even stranger is the high volume reported for the various 18-55 F/3.5-5.6 lenses. These usually come as kit lenses for crop cameras, why would anyone buy these separately?
  • I see lots and lots of people running around with crop camera plus superzoom, yet these don't seem to show up in the higher ranks.
  • The 16-35 shows up higher in rank than the 17-40. Sounds bogus if you ask me.
  • The 70-200 F/4 showing up lower in rank compared to the 70-200 F/2.8 also strikes me as odd. All people I know with a 70-200 F/2.8 have the IS version, either Mk I or Mk II.

Obviously I don't have any insight into Amazon's sales numbers, and I don't run or work in a photo store to provide real world numbers, but I think Amazon's reported numbers raise more questions than they answer.

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Lenses / Re: Review: Sigma 50mm f/1.4 DG HSM Art Lens
« on: Today at 08:49:36 AM »
It's not about the lack of skills, it's matter of not violating patents Canon own.

Canon made fast EF compatible glass over 17 years ago, all relevant patents must have expired by now, if they ever existed. A few years ago there was a long thread in some german photo forum about the Canon EF lens protocol and the way Sigma reverse engineered it. The conclusion was that Sigma did not put much effort into it and as a result had AF problems that seemed to have pestered them forever. This may have been ok when they made mostly cheaper substitutes for Canon/Nikon accessories, but with their new ambition towards optical excellence they clearly have some homework to do.

I have been thinking about this also and I'm beginning to suspect that Canon has software in the body to prevent the third party lenses from focusing consistently. Basically if the camera does not recognize the lens as Canon it would insert random miss focusing.

Or alternately if the lens is miss identified by the camera as some other Canon lens, it is apply a correction which is appropriate for the Canon lens but not good for the Sigma.

If a Canon camera indeed introduced targeted random focus shifts for third party glass, then it would be fraudulent for third party manufacturers to sell lenses as fully functional. Somehow I doubt this, and the fact that so many people seem to be happy with third party accessories seems to confirm my doubt. But here's the thing: even if they perfectly reproduced Canon's protocol, if their HSM drive loses steps due to sticky surfaces or whatnot, they would have inconsistent focusing. Remember that regular AF is a single effort process. This would more likely explain why poor AF performance seems to be so random.

If the camera sends some lens specific corrections, these are either fixed parameters, or based on parameters sent by the lens to the camera. In both cases the lens should have full control how it responds to data sent by the camera.


If that came out to be true, a lot of people will lose what respect they had for Canon and the other manufacturers would jump on this.

The last major incident happened with the introduction of the 10D, when a range of Sigma lenses stopped working. It has been proven conclusively, that Canon introduced a pointless protocol change, just to become incompatible with Sigma lenses ("the work ain't done until Sigma won't run"). People still blame this on Sigma and only use it as a justification to stick to Canon accessories, even if it limits their options and, on average, is more expensive. Rarely do you see "bad Canon, stop messing pointlessly with your protocol!" postings.

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Lenses / Re: Review: Sigma 50mm f/1.4 DG HSM Art Lens
« on: Today at 05:26:43 AM »
I really wonder what is so damn hard about reverse engineering that Canon lens protocol. We are not talking about some one man show running a startup on a shoe string budget and Ramen noodles, AFAIK Sigma is a sizable company that can design outstanding lenses. It's not like they'd have to crack AES encryption to make this work. They build up all this reputation for the new 50A, only to see it shredded by their poor electronics/firmware. 99-yard football seems to be their favorite sport ...

To those who wondered why AI works for the 50A and single shot AF doesn't (reliably): single shot AF is usually an one effort procedure: measure point spread, calculate AF motor movement, perform motor movement, done. If the measurement is off, or the motor does not move as intended, your AF will be off. With AI the measure/calculate/move procedure is performed continuously, and therefore will only fail in focus shift situations (see 50L).

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Third Party Manufacturers / Re: Dissuade me to get a Rolleiflex
« on: April 19, 2014, 03:09:13 PM »
sootzzs, US$ 120 is not going to to get you very far in medium format, and you also need to take cost for film and processing into account. Shooting landscape with a cheesy camera will only disappoint you.

The cheapest way to get started is an analog EOS camera, that way you can use all your full format lenses and get started with film while you save up for a decent medium format camera.

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Lenses / Re: DxO Review of Sigma 50mm 1.4 DG HSM Art
« on: April 18, 2014, 04:34:05 AM »
It looks like they measure it across the frame, and they don't mention vignette compensation:


That would explain why a slow IS zoom like the 24-70 F/4 IS has T=4 whereas all fast lenses have T stop significantly above their largest aperture. In other words, this T stop number is a poor substitute for their vignetting number and as such should be considered most useless.

Very confused ...

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Lenses / Re: DxO Review of Sigma 50mm 1.4 DG HSM Art
« on: April 17, 2014, 11:20:29 AM »
Since all of these fast lenses have severe vignetting wide open, I wonder how they measure T stops. Do they measure average across the whole frame, or only in the center, or somewhere in between these two extremes?

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Haha, to all those who made fun of Canon with the alleged 75D with hypersvivel: Canon can be even less innovative than the most creative minds on the web can imagine!

If I was British, I would be insulted that they picked my country for this ugly abomination.

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Lenses / Re: Review: Sigma 50mm f/1.4 DG HSM Art
« on: April 16, 2014, 11:31:47 AM »
One key issue with the 50L is the "focus shift" that occurs if the lens is used near minimum focus distance at apertures between 2 and 4. Since this is quite a common setting in portrait shots, I wonder why so many people recommend the 50L so much as a portrait lens.

And the second thing which wonders me even more, is that none of these reviews checked whether the 50A suffers from this same focus shift issue. Since the issue appears to come from spherical aberrations which are less present in the 50A there is a good chance that the 50A is less affected, but the many tests and comparisons between 50L and 50A might as well take a closer look.

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Third Party Manufacturers / Re: Dissuade me to get a Rolleiflex
« on: April 14, 2014, 05:04:46 PM »
PS.: As a side question: except of the obvious advantage of the Medium Format resolution (is it really equivalent to 60 Mega pixel picture?) is there any advantage to the film (35mm or other) over a full frame DSLR (which I can't compare to)?
With a medium format camera you will quit counting megapixels very quickly. Assuming you buy a decent piece of equipment and use modern film and developers, you will have all the resolution you'll ever need, period.

What you will notice quickly once you get your analog process dialed in is that these films bring an incredible tonality and color palette out of the box. You think of the mood you want to create, pick the proper film and the result will look just right. In theory you could do all this in digital, but given the dreadful digital B&W images posted by self proclaimed professional photographers here in this forum, it seems to be a lot more difficult than it looks at the first glance, sometimes more options don't lead to better results.

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Third Party Manufacturers / Re: Dissuade me to get a Rolleiflex
« on: April 14, 2014, 06:05:57 AM »
If you enjoy TLRs and their way of shooting, by all means go for it. Since US$ 2k is a lot of money and can get you a wide range of very decent analog gear, I recommend you do some price shopping (look at keh and adorama), and maybe investigate the merits of possible alternatives, just to be sure.

Once you make the Lubitel-->Rollei upgrade, you may need some extra things that help you get optimal results: a decent exposure meter, a sturdy tripod and cable release, and ideally some equipment for processing exposed films yourself. Maybe check out whether there is a dark room available nearby wherever you live.

Even if some people here seem to hate film, the results will speak for themselves.

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Lenses / Re: Review: Sigma 50mm f/1.4 DG HSM Art
« on: April 14, 2014, 05:31:24 AM »
I´m really curious to see how it performs against 35 Art. I have seen a couple of reviews but it seems no one compares these two. Still waiting for the first user reports and then I´ll decide. I would prefer 35 before 50 focal length for my 5D3. But if this new 50 is optically better then I´ll probably change my decision. Only optical performance matters for me, I do not care about weight or size. Sharpness, CA, micro contrast, this is important for me.

I think Neuroanatomist explained this in some recent thread: most 35s use retrofocal design, whereas most 50s in the market (until recently) use a double gauss design. The double gauss design is simpler and more compact, but allows for fewer corrections and as a result gave lenses that were less than stellar in performance, especially wide open. Zeiss, and now Sigma, changed that by offering 50s as retrofocal designs, and as a result they now have 50s that blow the competition out of the water. But that means only the 50mm competition, other 35mm lenses always used retrofocal design and always had the opportunity to be decent performers.

So what do we have now: we have an outdated 35L that gets outclassed by a very modern 35A, but only by so much, the 35L wasn't all that bad after all. And we have a new 50A that makes its competitors look really old. That doesn't mean the 50A is going to be that much sharper/better than the 35A or the 35L. What the 50A does is give you the option to pick between a decent 50 and a decent 35. The final decision should (and can now) be made based on what focal length you want, not by some 2% difference in MTF ratings.

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Lenses / Re: Review: Sigma 50mm f/1.4 DG HSM Art
« on: April 13, 2014, 11:29:37 AM »
Interesting review, which covers many aspects that would be of interest to potential buyers of this lens. One line didn't make much sense, though: "Additionally, we feel that the saturation is a bit too strong for skin tones when shooting portraits despite Sigma’s attempts to not saturate the orange channel too much–at least that’s what we feel in our color tests."

A lens can't saturate colors beyond what's coming in through the front element. If the image looks too saturated, check and adjust your post processing settings and don't blame the lens for doing its job as intended.

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Third Party Manufacturers / Re: Tokina 24-70 f/2.8 Pro FX Spotted
« on: March 11, 2014, 04:09:25 PM »
I admire your patience, but personally I would not invest big money in gear that is unsupported in my country. If Sigma/Tamron/whoever are unable or unwilling to provide adequate service for their equipment in your place, they don't deserve your money. Software upgrades aren't the only reason you need a service center.
Then I cannot see how we disagree.  I agree with this 100%. And judging by the companies behavior in the past we have the right to act accordingly in the future...

Sigma's behavior 10 years ago should make everybody cautious, but not hysterical. We might as well ditch Canon for their less than smooth FD-->EF mount transition. Forfeiting a whole range of purchasing options because of some misgivings a decade ago is certainly within your rights, but it doesn't sound smart or cost effective.

BTW Rienzphotoz' case seems very special, AFAIK Sigma, Tamron and Tokina do provide service in most countries with a significant photographic market.

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Third Party Manufacturers / Re: Tokina 24-70 f/2.8 Pro FX Spotted
« on: March 11, 2014, 02:49:30 PM »
Even though you know "their existence is an old and well known fact" you felt the need to post it, but when others also mention it you feel the need to be sarcastic ... how logical ::)
I posted these old news in reply to a posting which perpetuated the old "I won't get upgrades if Canon plays silly again" meme, and the sarcastic tone (stemming from the obvious contradiction between my praise for the other guy's invention paired with the links to already existing products implementing that very feature) was another futile attempt to put that meme to rest for good. Read tron's posting immediately before my first one in this thread and then mine to get the context.

Every single one of those lenses developed some issueor another with AF or OS/VC after upgrading to a new camera or firmware, they would suddenly start hunting for auto focusing on a subject or the image stabilization would take longer to be activated and/or drain the battery with the OS/VC on even when they were not being used ... were they useless? absolutely not, coz I could still get great images with every one of them (except the Rokinon T/S, which was just a sh!tty lens from the beginning) but the issues they developed were annoying. I am sure a visit to the the third party manufacturers service center will fix those issues, but (as mentioned earlier) where I live there is no service center for third party lens manufacturers

I admire your patience, but personally I would not invest big money in gear that is unsupported in my country. If Sigma/Tamron/whoever are unable or unwilling to provide adequate service for their equipment in your place, they don't deserve your money. Software upgrades aren't the only reason you need a service center.

1. Put it to rest and spend your money. Then if something breaks wait for the 3rd party companies to really change the firmware...
Funny thing is all the pros I see rarely have brand new gear with them. It's usually wannabe amateurs who need the latest and greatest the minute it hits the market, when it is sold at a premium and hasn't received thorough testing yet.

With a few months of patience you can save 20+% on camera bodies AND can use cheaper third party accessories.
3. I do not recall reading about other 3rd party manufacturers doing the same as Sigma...
  • Metz flashes come with a USB connector for firmware upgrades. My first post in this thread links to the relevant page
  • Sigma received the most heat during the last decade, because in 2003 (release of the 10D) a long list of lenses in their lineup could no longer be used on Canon's latest and greatest, and Sigma decided to throw their customers under the bus. They seemed to have learned their lesson lately and want to be seen not as cheap alternative but as viable and well reputed alternative. Since that Err99 debacle is still in people's minds, Sigma had to come up with a viable option for simple upgrades.

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Lenses / Re: Sigma ART Series: 70-200mm f2.8 possible?
« on: March 11, 2014, 12:53:20 PM »
The street prices I see for the Sigma 70-200 F/2.8 have come down a lot lately, and I would assume they had to cut their prices to stay competitive with Tamron's new 70-200, and especially the used price of Canon's 70-200 Mk I.

Sigma more or less has to come up with a new (and better) 70-200, if they want to stay in that market ... BTW the same is true for their 24-70.

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