# Is the Sigma 35 supposed to be as sharp as the 70-200L?



## sunnyVan (May 21, 2013)

A lot of people say the Sigma is razor sharp. It just isn't nearly as sharp as my 70-200L. It is only as good as my 50 1.4. Don't get me wrong. I think it's not bad. It's just not as sharp as I was hoping. Things look nice on LCD but come out slightly disappointing on monitor. Its AF seems slow too, not as snappy as I wanted. I've never used the 35L so I can't compare. Am I expecting too much? After all, a wide angle is more difficult to make than a tele. Do people really sell their 35L to get this? Well, maybe I have a bad copy...


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## neuroanatomist (May 21, 2013)

Assuming you mean the 70-200/4L IS in your sig, no, the Sigma 35/1.4 isn't as sharp as that lens, not wide open and not stopped down by the same relative amount. With both at f/4 (therefore, one stopped down and the otehr wide open), the Sigma still isn't quite as sharp. 

But compared to the Canon 35/1.4L, the Sigma is sharper and has less CA - especially wide open. If I was buying a 35/1.4 lens today, it'd be a tough choice between a bit better IQ and faster and possibly more accurate AF. But I bought the 35L well before the Sigma came out, and have no plans to trade. I'll wait for the 35L II, with optics that top the Sigma lens and weather sealing too...and I'll pay the premium.


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## helpful (May 21, 2013)

Yes, it is supposed to be as sharp. (Note that this compares Nikon vs. Canon versions, but results should be comparable because they're using the old D3s to evaluate the Nikon lens.)

http://www.photozone.de/nikon_ff/792-sigma3514dgfx?start=1
http://www.photozone.de/canon_eos_ff/510-canon_70200_2is28?start=1

At f/1.4 the Sigma ranges from 3K to 3.2K. And at f/2.0 the Sigma ranges from 3K to 3.7K. At f/2.8 the Sigma ranges from 3.2 to almost 3.9K (line widths per picture height).

At f/2.8 the Canon 70-200 ranges from 3.1K to 3.5K. The all around peak of the Sigma is 3,960 @f4.0 while for the Canon it is 3,721 at f/5.6 at 70mm.

Remember that the resolution of the Sigma is not as dramatic as the zoom lens because the zoom lens makes everything look closer and therefore seem much sharper. Objects will look more blurry with the Sigma lens because they take up a smaller number of pixels unless you are 5.7 times closer. In other words, the resolution of the 70-200mm will seem higher for a picture taken at 50 feet away than the 35mm will for a picture taken around 8 feet away. The apparent resolution increase of the 200mm lens is 5.7^2 = about 32 times higher apparent resolution for the same object photographed at 200mm vs. 35mm.


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## neuroanatomist (May 21, 2013)

helpful said:


> Yes, it is supposed to be as sharp. (*Note that this compares Nikon vs. Canon versions, but results should be comparable because they're using the old D3s to evaluate the Nikon lens*.)
> 
> http://www.photozone.de/nikon_ff/792-sigma3514dgfx?start=1
> http://www.photozone.de/canon_eos_ff/510-canon_70200_2is28?start=1
> ...



Ummmm....no. Ignore for the moment the fact that Klaus specifically states, "Please note that the tests results are not comparable across the different systems." The Sigma 35/1.4 was not tested on 'the old D3s' (a 12 MP FX camera) but on the D3x, a 24 MP FX camera. Those extra 3 MP directly translate to an increase in LW/PH compared to the 21 MP Canon 5DII, all else being equal. 

Compare the TDP ISO 12233 crops (where the Canon version of the Sigma lens was tested on the same camera as the Canon lens), is the Sigma as sharp? Nope.


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## wickidwombat (May 21, 2013)

sunnyVan said:


> A lot of people say the Sigma is razor sharp. It just isn't nearly as sharp as my 70-200L. It is only as good as my 50 1.4. Don't get me wrong. I think it's not bad. It's just not as sharp as I was hoping. Things look nice on LCD but come out slightly disappointing on monitor. Its AF seems slow too, not as snappy as I wanted. I've never used the 35L so I can't compare. Am I expecting too much? After all, a wide angle is more difficult to make than a tele. Do people really sell their 35L to get this? Well, maybe I have a bad copy...



i would say my sigma 1.4 is as sharp as my 2 copies of 70-200 mk2 at 1.4 vs the zoom at 2.8

by f2 to f2.8 its way sharper

but they are very different lenses with different characteristics


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## Viggo (May 21, 2013)

sunnyVan said:


> A lot of people say the Sigma is razor sharp. It just isn't nearly as sharp as my 70-200L. It is only as good as my 50 1.4. Don't get me wrong. I think it's not bad. It's just not as sharp as I was hoping. Things look nice on LCD but come out slightly disappointing on monitor. Its AF seems slow too, not as snappy as I wanted. I've never used the 35L so I can't compare. Am I expecting too much? After all, a wide angle is more difficult to make than a tele. Do people really sell their 35L to get this? Well, maybe I have a bad copy...



I was also very dissapointed in the AF-performance of the Siggy. I own the 35 L, after talking to a few people, I seem to have a very nice copy of it as it is very sharp at 1.4 and the AF is of the best I have owned and currently own, except the insane 70-200 mkII of course. 

This is shot at 1.4:


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## Nishi Drew (May 21, 2013)

Maybe I just don't crop in to insane levels but the lens looks plain sharp wide open, never had any problems with missing focus either, with other Canon glass I needed AFMA but no need with this.
Then again, I don't have any sharper glass, the Canon 50mm 1.4 is stopped down, but that lens isn't much of a joy to use in comparison, especially with IQ in general


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## helpful (May 22, 2013)

neuroanatomist said:


> helpful said:
> 
> 
> > Yes, it is supposed to be as sharp. (*Note that this compares Nikon vs. Canon versions, but results should be comparable because they're using the old D3s to evaluate the Nikon lens*.)
> ...



Your correction about the D3s vs. D3x is valuable. I meant to write D3x and I was thinking of that model, but out of habit without noticing my fingers typed D3s.

However, my respect went down (a little) for you, neuroanatomist, because you suggest ignoring Imatest results in favor of subjective pictures which, no matter how carefully made, cannot be used for valid comparison.

It makes no difference whether it was an ISO 12233 chart, whether was originally shot in RAW, whether it was made on concrete floor with a $25K setup, etc.

All those things may be true, and yet the sharpness selected on output has more to do with how sharp it looks to our eyes than even a 33% difference in lens sharpness. Also, I know for a fact that some of the cheaper lenses were not properly focused on the point shown in the cropped image area, by accident, I'm sure (I know that it is an immense time sacrifice, and I am not trying to criticize TDP in any way) while the more expensive lenses like the 200mm f/2.0 were properly focused. That alone makes a night and day difference when pixel peeping.

Additionally, some of the lenses shown by TDP have curvature of field which makes them look more blurry than they would if a focus point was actually used to focus at that point in the frame. This is just another reason why looking at a photo and allowing our imperfect senses to judge sharpness just doesn't work.

As a case in point, the Canon 85mm f/1.8 images show terrible softness in the images at TDP (they never look anywhere near as sharp as some of the other lenses do, even when stopped down to f/8!), but I know for a fact that they are not so bad.

Once again, I know that it is an immense time sacrifice to make those visualizations of lens quality, and I am not trying to criticize TDP in any way. But I am urging that *proper scientific metrics should be used when discussing lens sharpness*, not looking at a subjective picture and saying, "Nope."

We have to use logic first before allowing ourselves to make a decision based on a picture. Case in point: Some disreputable websites have for years used a sleight of hand trick to "prove" to people that RAW is sharper, by using "default" sharpening on JPEG output that is actually a lot weaker than the "default" sharpening used for RAW. Saying that RAW is sharper makes no more sense than saying that RAW has better white balance. Yes, RAW has more data in it to be used for any purpose, but both the sharpness and white balance are determined by processing after the fact. (You can never see RAW data. You can only see a visualization of RAW data.) So any comparison saying RAW is sharper than JPEG is by definition a comparison of two different levels of sharpening of RAW data and therefore make no logical sense other than to say that one amount of sharpening looks different from another. The same is true for comparing sharpness of lenses subjectively by looking at pictures on a website with our eyes. It just makes no sense.


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## neuroanatomist (May 22, 2013)

The point is, test results are not comparable across different systems. Maybe it's the scientist in me, I just seem to have this innate tendency to ignore results from test methodologies which are not valid, and to ignore conclusions based on invalid interpretations of the data. I don't really understand how you can state the results 'should be comparable,' when the person who did the testing states explicitly that they are not. If you had cited photozone data to support the conclusion that the 85L II was sharper than the 85L, I would 'ignore' those results, too, since the former was tested on the 50D and the latter was tested on the 350D. If/when Klaus tests the Canon mount version of the Sigma 35/1.4, we can use those data as a _valid_ comparison.


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## bholliman (May 22, 2013)

helpful said:


> I know for a fact that some of the cheaper lenses were not properly focused on the point shown in the cropped image area, by accident...while the more expensive lenses like the 200mm f/2.0 were properly focused. That alone makes a night and day difference when pixel peeping.



TDP is one of the most universally respected photography review websites. Sounds like you have hard evidence that they are "by accident" using different test methods to make more expensive equipment look better. That's a pretty strong accusation!

Please share your evidence.


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## SambalOelek (May 22, 2013)

sunnyVan said:


> A lot of people say the Sigma is razor sharp.* It just isn't nearly as sharp as my 70-200L. It is only as good as my 50 1.4.* Don't get me wrong.



But the 50mm f/1.4 is noticeably sharper than the 70-200 f/4 IS... at comparable apertures. The 50mm is only moderately sharp wide open, but at f/2.0 it's already very sharp. From 2.8 to 5.6 it will outresolve most zoom lenses, including the 70-200 f/4 IS. 

Tests indicate the Sigma 35mm f/1.4 has a similar characteristic. I would not expect it to be as sharp as the 70-200 f/4 IS from f/1.4


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## pdirestajr (May 22, 2013)

They are both "sharp".


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