Review - Sigma 20mm f/1.4 DG Art

Random Orbits said:
Larsskv said:
Random Orbits said:
The 20A is a good lens, but it is clearly not superior to other options near the same focal length as the 35A and 50A were when they first came out.

I can´t see that the 20A has any competitors. The f/1.4 on 20mm is unique.

And speeking of coma, one might expect too much. It must be hard to overcome. Is there any 24mm f/1.4 lenses with good coma control? Maybe the Samyang? The Canon 24LII isn't good at all when it comes to coma.

Disagree, I think many people will compare the 24 primes to the 20A. How many people will have a fast 24mm prime AND the 20A? I can't imagine that that population would be very large at all. But I can see people having the 20A in place of a 24.

Sigma set up the expectation on coma for the 20A. It it's press release for the 20A:

Allowing the photographer to leverage the perspective provided by the wide-angle and the shallow depth of field provided by the large aperture, this lens is ideal not only for such ultra-wide-angle subjects as landscapes and starry skies, but also for snapshots in low light, indoor photography, portraits with a natural bokeh effect, and much more.

...

Moreover, SIGMA’s advanced optical design minimises distortion, transverse chromatic aberration, sagittal coma flare, and the reduction of brightness toward the edges of the image. Delivering top performance even at wide-open aperture, this lens can be considered the culmination of SIGMA’s Art line.

I read it somewhat differently as they never specifically/explicitly state that it is better than others at 1.4 for astro. Their statement can be construed such that they are saying the lens performs well wide-open for a variety of things (which it does). Also, stopped down just a little bit, while still being faster than the competitive 2.8 lenses that are wider than 24mm, it still performs very well.

Furthermore, there is no way of knowing whether it is better than the other lenses in its class at 1.4 since it stands alone at this focal length and aperture combination. So it wouldn't actually be false even if they came out and said that it performs the best at astro at 20/1.4 since you can't actually do that with any other lens.

https://fstoppers.com/originals/sigma-20mm-f14-art-special-astronomy-review-104169

That's just one I found quickly. But there are plenty of other tests around the net also that show how well it actually performs even when compared with lenses that are not as wide.
 
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ahsanford said:
Larsskv said:
Random Orbits said:
The 20A is a good lens, but it is clearly not superior to other options near the same focal length as the 35A and 50A were when they first came out.

I can´t see that the 20A has any competitors. The f/1.4 on 20mm is unique.

And speeking of coma, one might expect too much. It must be hard to overcome. Is there any 24mm f/1.4 lenses with good coma control? Maybe the Samyang? The Canon 24LII isn't good at all when it comes to coma.

The 24L III might be, if it has that BR gunk in it (which we assume it will).

Consider: the coma on the 35L vs. the coma on the 35L II is night and day better.

Agree that folks are being really hard on this 20mm lens. Whereas the 35 and 50 Art mopped the floor resolution-wise vs. its Canon counterparts, here at 20mm f/1.4, nothing else is offered to compare it to. You have the choice of some UWA primes at f/2.8 or the 24L II, but they aren't exactly apples to apples comparisons.

I just think everyone is whinging about the coma as -- with no surprise -- this would have been a legendary / staple / first-choice astro lens otherwise.

- A

+1. I think the Tamron 15-30 is becoming a very choice for astro because of its low coma but having a filterable 24mm f/1.4 III that does as well as the 35L II WRT coma would be very interesting.
 
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Larsskv said:
From my experience so far, I find the AF on the 20A to be very acceptable on my 5Ds.

I have reservations about wide aperture Sigma AF based on my 35 Art rental tryout (after I docked/calibrated it) and with the widely reported 50 Art AF inconsistency problem, but I may cool my jets a bit on this particular lens.

I'd largely be using this lens on a tripod with Liveview manual focusing if I owned it, so I'd be far less concerned about AF work.

Further, if I was off the tripod, unless I was shooting point blank cows-nose-in-pasture shots, the wider FL buys you far more latitude for the AF to miss than, say, a 50 Art would have. Using this lens for environmental portraiture @ f/1.4 at (say) 10 feet away would have something like 7 feet of working DOF -- the AF would have to be horrendous to pooch it that badly. (Someone correct me if I've got that wrong, that's not typically what I shoot, thx.)

- A
 
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slclick said:
blanddragon said:
Looks like you touched some kind of fanboi nerve Dustin. For what it's worth I always enjoy your perspective because it saves me from G.A.S (slightly).

I find it interesting there has been no thread or comments on Dustin's 50L review a few days back. That is truly a lens with some strong opinions.

Because the 50L has been covered ad nauseam. You love it or you hate it like one always/never uses a UV filter. More debate won't change opinions on it.

This 20 Art, however, is an odd duck that we've never seen before. Discuss! :D

- A
 
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JohnDizzo15 said:
Random Orbits said:
Disagree, I think many people will compare the 24 primes to the 20A. How many people will have a fast 24mm prime AND the 20A? I can't imagine that that population would be very large at all. But I can see people having the 20A in place of a 24.

Sigma set up the expectation on coma for the 20A. It it's press release for the 20A:

Allowing the photographer to leverage the perspective provided by the wide-angle and the shallow depth of field provided by the large aperture, this lens is ideal not only for such ultra-wide-angle subjects as landscapes and starry skies, but also for snapshots in low light, indoor photography, portraits with a natural bokeh effect, and much more.

...

Moreover, SIGMA’s advanced optical design minimises distortion, transverse chromatic aberration, sagittal coma flare, and the reduction of brightness toward the edges of the image. Delivering top performance even at wide-open aperture, this lens can be considered the culmination of SIGMA’s Art line.

I read it somewhat differently as they never specifically/explicitly state that it is better than others at 1.4 for astro. Their statement can be construed such that they are saying the lens performs well wide-open for a variety of things (which it does). Also, stopped down just a little bit, while still being faster than the competitive 2.8 lenses that are wider than 24mm, it still performs very well.

Furthermore, there is no way of knowing whether it is better than the other lenses in its class at 1.4 since it stands alone at this focal length and aperture combination. So it wouldn't actually be false even if they came out and said that it performs the best at astro at 20/1.4 since you can't actually do that with any other lens.

That might have been true before the Tamron 15-30. Dustin's review shows that even stopped down nearly two stops, the 20A still loses to the Tamron for coma. And sure, for a unique lens, you can claim that it can do the best in class for anything, but how far will that get you the next tell you try to promote your next product? It would have been better if they just left out starry skies and the coma bit all together. Naturally once the announcement was made public, threads started appearing on CR about how it could be the next great astro lens but then the reviews came out and the enthusiasm here was dampened quite a bit. For astro alone, I think the Tamron wins out over the 20A. Both are unfilterable and the Tamron gives you more framing options and better performance. So then the question comes down to whether or not one prefers the 15-30mm focal length range and better astro performance or 2 stops at 20mm and I think many will choose the 15-30.
 
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One of my most favorite lenses EVER!
Love the perspective, the IQ, and the creative nuance of an f/1.4 at this focal length........ weather sealing, coma and no-filters be damned! This lens ROCKS! (I don't shoot Astro, but I do not believe, at this time, that any manufacturer could make a lens at this focal length, and have no coma @ f/1.4, at least a lens that would be affordable).
I think that this lens is especially fantastic at this price point, for what it does offer.
I guess that I qualify as a niche guy! :-)

Out of my 3 Art Lenses, (50mm & 35mm, too)...this one is by-far my favorite.
 
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Front filtering will come on this lens eventually -- Wonderpana or Lee will eventually make an adaptor sleeve to allow their mondo UWA outrigger setup to work on it. If they can get it to work on the 11-24 f/4L, it will work for the Sigma 20 Art.

- A
 
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ahsanford said:
slclick said:
blanddragon said:
Looks like you touched some kind of fanboi nerve Dustin. For what it's worth I always enjoy your perspective because it saves me from G.A.S (slightly).

I find it interesting there has been no thread or comments on Dustin's 50L review a few days back. That is truly a lens with some strong opinions.



Because the 50L has been covered ad nauseam. You love it or you hate it like one always/never uses a UV filter. More debate won't change opinions on it.

This 20 Art, however, is an odd duck that we've never seen before. Discuss! :D

- A

Yet CR decides to create buzz and emails a 'Special' Members Only review access point. Oh and when has ad nauseam ever stopped discussion here?
 
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slclick said:
Stephen Melvin said:
He really seems to gloss over the AF issue with this lens, not even listing it as one of the "cons." As somebody who used to buy and use a lot of Sigma lenses, I have to say that AF is something that is always my first question when Sigma introduces a new lens. I think I've had 1 out of 5 Sigma lenses that AF right. I no longer own any Sigma lenses, because they still don't know how to make the things autofocus. Even on a 20mm lens! Astonishing.

Also, "perspective distortion" isn't the stretching in the corners. PD is what happens when a camera is close to the subject and the subject looks distorted to the viewer. An enlarged nose, for example, when taking a photo at extreme close range. Even a 50mm lens can be used to take a photograph with perspective distortion. It's the distance, not the lens, that creates perspective distortion.

There's a reason the classic portrait lenses are from 85mm to 135mm.

I'm curious if you have had a chance to try or own any of the Art lenses? They are much better than the EX line in terms of copy variation, AF speed and consistency.

I haven't, but Dustin's review mentions AF issues. Lack of consistency. AF issues in the midrange. Every issue I've seen in almost every Sigma lens I've owned.

A friend bought one of the Art lenses. Absolutely loved it for about a month. And then the AF failed. A single point of data by itself, but when I add it to my own experience with Sigma lenses, they're batting .200 at best.

If they could get their electronics working as well as their optics, which have improved tremendously, then I'll take another look at them.

I've never had a Canon, Tamron, or Tokina lens fail on me.

The fact that they introduced the "dock" (shifting QC from the manufacturer to the consumer) speaks a lot about them. I can't tell you how many times I've sent lenses back to Sigma, only to have them say they were "in spec." "Send up your camera," they said. I did. It came back with no protection whatsoever - it just sat in the bottom of the box. And the lens still wasn't fixed.

My 50-150 f/2.8 never did AF correctly. It got even worse when the flex board failed (which happened to another Sigma lens I owned), shortly after the warranty expired. It actually did AF accurately once Canon introduced the 7D and I was able to adjust focus manually. +20 was the adjustment.

I was very excited when Sigma announced the 20 f/1.4. But I've been waiting for reviews. Dustin's generally positive review mentioned all of the same AF issues Sigma has had for the past dozen or more years. If you're shooting at f/1.4, you need focus to be spot on. I'll pass.
 
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Random Orbits said:
That might have been true before the Tamron 15-30. Dustin's review shows that even stopped down nearly two stops, the 20A still loses to the Tamron for coma. And sure, for a unique lens, you can claim that it can do the best in class for anything, but how far will that get you the next tell you try to promote your next product? It would have been better if they just left out starry skies and the coma bit all together. Naturally once the announcement was made public, threads started appearing on CR about how it could be the next great astro lens but then the reviews came out and the enthusiasm here was dampened quite a bit. For astro alone, I think the Tamron wins out over the 20A. Both are unfilterable and the Tamron gives you more framing options and better performance. So then the question comes down to whether or not one prefers the 15-30mm focal length range and better astro performance or 2 stops at 20mm and I think many will choose the 15-30.

Horses for courses with regard to the Sigma or the Tamron zoom. They are both very different tools with very different potential uses IMO. The Sigma, at least for me, is one of those lenses that does a lot of things in a way that makes it very distinct from everything else from rendering to usability. The Tamron is also an awesome lens, but in its own way which is completely separate/independent and without comparison to the Sigma. Astro is merely one facet of shooting, and is very low on the totem pole of priorities for many of us that own and run the Sigma. Furthermore, when I do decide to do some astro with a wide lens, I'm certain the level of coma in this lens will not dampen my overall delight with it.

Not sure how these other lenses perform at the unique extremes, but I would venture to say that I'm fairly certain the 11-24L can be beaten in some aspects at 11mm by various other lenses close to that focal length in some metric. The 17 TSE can also be beaten in some aspects by other lenses that are close in focal length. But none of those metrics matter when it comes to owners of those lenses.

If the 20 Art were solely advertised as the breakthrough lens for astro, then fine. I would accept that it was an overstatement and stretch by Sigma. But to my knowledge, what they have said does not reflect that. If anything, I believe it is more inference from people around the net that built up excitement for it for astro that attributed to that perceived claim rather than what was actually stated by Sigma.
 
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JohnDizzo15 said:
That might have been true before the Tamron 15-30.
[truncated]

Yes, but a 15-30 f/2.8 IS lens like the Tamron can do many things -- events, sports, macro, video, etc. -- and yet despite the fact it seems aimed for the 16-35 f/2.8 events/sports shooter, somehow it surprisingly does very well for astro from what I've read. This is like having a standard zoom that has a serviceable macro mode -- it's not why you bought it, but wow, that's a nice add.

But the Sigma 20mm f/1.4 doesn't get that same benefit of the doubt. It drops the ball on one of the two critical things you'd expect it does well -- coma for astro and general rendering for environmental portraiture. Astro folks probably ought to be bent out of shape about this.

So astro with the Sigma seems (to me) to be a core expectation of the lens, yet it doesn't deliver as well as one would hope. But the Tamron fares well in astro and it is not even the 1st, 2nd, or 3rd thing you'd expect people would be buying that lens for!

- A
 
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ahsanford said:
JohnDizzo15 said:
That might have been true before the Tamron 15-30.
[truncated]

Yes, but a 15-30 f/2.8 IS lens like the Tamron can do many things -- events, sports, macro, video, etc. -- and yet despite the fact it seems aimed for the 16-35 f/2.8 events/sports shooter, somehow it surprisingly does very well for astro from what I've read. This is like having a standard zoom that has a serviceable macro mode -- it's not why you bought it, but wow, that's a nice add.

But the Sigma 20mm f/1.4 doesn't get that same benefit of the doubt. It drops the ball on one of the two critical things you'd expect it does well -- coma for astro and general rendering for environmental portraiture. Astro folks probably ought to be bent out of shape about this.

So astro with the Sigma seems (to me) to be a core expectation of the lens, yet it doesn't deliver as well as one would hope. But the Tamron fares well in astro and it is not even the 1st, 2nd, or 3rd thing you'd expect people would be buying that lens for!

- A
Again though, it's different strokes for different folks. Both of these lenses offer a lot and in very different ways. If you need the flexibility of zoom and astro is your thing, then the Tammy seems to be perfect. Nothing wrong with that. But if you're like me and want unique rendering, large aperture, and generally good sharpness at those wide apertures, then the Sigma is it. I personally run it on an A7R2 so it is a stabilized 20mm 1.4 which opens up a lot of doors for what I like to shoot that were previously much harder or impossible. I'm certain the Tamron is awesome and much more useful for many people out there, but we must remember there are hundreds of thousands of us shooters out there with an infinite number of varying needs.

Also, the conversation keeps going in the direction of inferring that the Sigma has really bad coma correction performance which is simply untrue. It may not be at the top in this regard, but it is certainly more than competitive. All this really proves is that the Tamron 15-30 is stellar at coma correction but not necessarily that the Sigma is bad.

Regarding potential uses as a macro. The magnification difference between the two lenses is there, but not huge in real-world use as the Tammy only gets you to 1:5 with the Sigma at 1:7 (both of which are not anywhere near true macros).

I often use it for pseudo macro stuff like this which more than satisfies my need.
 

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TWI by Dustin Abbott said:
Funny how so many photographers rip on 6D, 70/80D, etc... because they "don't" have "pro-grade" weatherproofing (not true, BTW).
I don't know whether many photographers rip on these prosumer-level cameras, as Canon sells a handful, but I certainly do. Photographing on the water a significant part of the year, I've learned that the weather sealing of anything less than a 1D-series camera will not do. Even then I occasionally ruin a $6-8,000 body.
Some years back, I tried using a 5D2. I was actually scared it wouldn't last through the first regatta, and we're talking the spray from only two or three foot waves, in no more than 15-knot breezes and just a couple miles offshore.
But, bodies seem to fail much more frequently than lenses. The nice thing about this one is that it will at least fit in an underwater housing.
 
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Andyx01 said:
Luds34 said:
dilbert said:
TWI by Dustin Abbott said:
...
but there is also a reason that more and more lenses are coming with weather sealing (including Zeiss repackaging a number of their lenses in new bodies with it). I think it is more than marketing. Yes, you should always use good judgment in protecting your gear, but some help from the lens is always welcome.
...

They spend, what, 10 cents more on production to put a bit of foam in there and get to charge $hundreds more?

You're right, it is more than marketing, it is money making because a little bit of effort adds a lot to the price that punters will pay.

You think so? I dunno. The only way we'd know for sure is if the exact same lenses existed in the two versions, weather sealed, and not. I know that I personally wouldn't pay any more for the weathered seal version.

Weather sealing is more marketing then anything else. Nothing is black and white. All various levels of grey. Just use your gear and be smart about it. I don't mind some misting, snow, etc. but you won't see me sitting outside in a hard rain either.

You're an idiot if you wouldn't pay $0.99 for weather sealing.
You're an idiot if you think you can out-protect the weather seal with your ninja reflexes and preparation.
One of my bodies got wrecked by a rouge wave simply splashing onto the bag my camera was in.
I didn't even think it got wet, but pulled the battery to be pro-active. It wasn't until I re-inserted the battery a few days later that I discovered the body was wrecked.

Spend the $0.99.

Ahhh yes, I'm the idiot. ::)

So you ruined a body because it was drenched in water, let me guess, a non weather-sealed one. Oh, but only if it were, then your camera would have been 100% fine! Ahhh the pain! I love anecdotal stories, so much better than statistical analysis or engineering design or even a little common sense. But fear not, many individuals who make a living in marketing thank people like you every day.

I bet you're one of those people who see the label "organic" slapped on something and that instantly holds a different meaning.
 
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dilbert said:
Luds34 said:
...
So you ruined a body because it was drenched in water, let me guess, a non weather-sealed one. Oh, but only if it were, then your camera would have been 100% fine! Ahhh the pain! I love anecdotal stories, so much better than statistical analysis or engineering design or even a little common sense. But fear not, many individuals who make a living in marketing thank people like you every day.
...

If you read Canon documentation you will find that "weather sealed" does not mean "water proof." The two terms are completely different.

Or if you feel confident that a "weather sealed" camera is "water proof" (can stand waves, etc), why don't you demonstrate it by putting your "weather sealed" camera/lens in a water bath (submerge it) and take it out again.
At least Olympus seems to think that you can do so (without submerging):
https://www.youtube.com/watch?v=fhO9YDI8cHk&feature=related

And users try submerging in a geothermal bath (at about 0:55):
https://www.youtube.com/watch?v=SfxUHGziwgg

Disclaimer: Don't try this at home! Don't try this with Canon equipment! (PowerShot D should work) ;)
 
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dilbert said:
Maximilian said:
...
At least Olympus seems to think that you can do so (without submerging):
https://www.youtube.com/watch?v=fhO9YDI8cHk&feature=related
...

Well then if you really want "weather proof" gear, buy Olympus :)
Honestly, when I was about to start over again today Olympus would be set very high in my choice list.
They have a great system of bodies and lenses. Only the user interface is a bit about getting used to.
Today, after several years of using a FF body I wouldn't go that road because of all the benefits I know now from having a FF sensor.
 
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dilbert said:
Maximilian said:
...
At least Olympus seems to think that you can do so (without submerging):
https://www.youtube.com/watch?v=fhO9YDI8cHk&feature=related
...

Well then if you really want "weather proof" gear, buy Olympus :)

Like that video proves anything. Many of you must have seen it before, the legendary DRTV durability test of the 7D:

http://youtu.be/RCT-YMgjm9k
 
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infared said:
One of my most favorite lenses EVER!
Love the perspective, the IQ, and the creative nuance of an f/1.4 at this focal length........ weather sealing, coma and no-filters be damned! This lens ROCKS! (I don't shoot Astro, but I do not believe, at this time, that any manufacturer could make a lens at this focal length, and have no coma @ f/1.4, at least a lens that would be affordable).
I think that this lens is especially fantastic at this price point, for what it does offer.
I guess that I qualify as a niche guy! :-)

Out of my 3 Art Lenses, (50mm & 35mm, too)...this one is by-far my favorite.
+1. This lens has been a joy to use, especially because the photos I get from it keep surprising me. There truly is nothing else like it.
 
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