# Review - Sigma 20mm f/1.4 DG Art



## Canon Rumors Guy (Apr 14, 2016)

Discuss our review of the Sigma 20mm f/1.4 DG Art here.


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## jeffa4444 (Apr 14, 2016)

Its interesting to note the view on "weather sealing". Many professional lenses for cinematography which run many hundreds of thousands of $$$ more do not have weather sealing and nor do most motion picture cameras. They are used in hostile conditions and by & large with the exception of very fine dust remain OK because crew take precautions to protect the equipment. 
Any sensible photographer is not going to leave even weather sealed lenses or cameras out in the rain they are not completely weather proof and its not ideal operating wet equipment. Humidity doesnt respect weather sealing and fine dust is almost impossible to eliminate getting into a lens given lenses rack in & out or are exposed at the rear when dismounted from cameras. 
Weather sealing limits the effects of the environment but we should never assume it eliminates those effects.


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## AWR (Apr 14, 2016)

That's right. This "review" is a really a cliche.
In photography those "cons" will be overtaken by good photographer in a millisecond.
I think this "review" has more to do with marketing Canon's new 16-35mm launch.


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## Larsskv (Apr 14, 2016)

Another great review from Dustin, although I don't think the need for weather sealing is that important, for what I do. 

I bought the 20mm ART mainly for northern lights shooting. It is amazing and unparalleled for that purpose. For good shoots of the northern lights, the shutter speed shouldn't be longer than 3-4 seconds. Having 2 stops advantage over an f/2.8 lens makes a very big difference, especially when shooting the 5Ds, when I want to keep the ISO low.


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## TWI by Dustin Abbott (Apr 14, 2016)

AWR said:


> That's right. This "review" is a really a cliche.
> In photography those "cons" will be overtaken by good photographer in a millisecond.
> I think this "review" has more to do with Canon's coming 16-35mm launch.



Seriously? There's not even a real release date nor price on that lens (16-35mm), but it will surely cost probably close to 3 times as much. I doubt too many photographers will be cross shopping those lenses.

In your opinion those cons may not be a big deal, but I have had dozens of photographers write me about gear recommendations but refuse to buy a lens without the ability to do traditional filters, or weather sealing, or because of poor coma control. They may not matter to you...but do matter to a lot of photographers.


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## TWI by Dustin Abbott (Apr 14, 2016)

jeffa4444 said:


> Its interesting to note the view on "weather sealing". Many professional lenses for cinematography which run many hundreds of thousands of $$$ more do not have weather sealing and nor do most motion picture cameras. They are used in hostile conditions and by & large with the exception of very fine dust remain OK because crew take precautions to protect the equipment.
> Any sensible photographer is not going to leave even weather sealed lenses or cameras out in the rain they are not completely weather proof and its not ideal operating wet equipment. Humidity doesnt respect weather sealing and fine dust is almost impossible to eliminate getting into a lens given lenses rack in & out or are exposed at the rear when dismounted from cameras.
> Weather sealing limits the effects of the environment but we should never assume it eliminates those effects.



All you have said is true...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.

Funny how so many photographers rip on 6D, 70/80D, etc... because they "don't" have "pro-grade" weatherproofing (not true, BTW).


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## AWR (Apr 14, 2016)

If the shoe fits...


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## TWI by Dustin Abbott (Apr 14, 2016)

AWR said:


> If the shoe fits...



LOL. I think the reason I wrote was to say that it didn't fit, but you, of course, are entitled to your opinion. That lens is not even on my radar yet.


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## AWR (Apr 14, 2016)

Let's be honest here. You, Canon Rumors, are very important part of Canon's marketing.

All the "insider tips", which no one else gets.
Exclusive launch stories.
Expensive Canon L-lens giveaways.

Canon this, Canon that, Canon everywhere on this site. And that's okay, that's why I come here. After all, most of my gear comes from Canon.
But this to be trustworthy review site, HA! 
I don't for one second think, that you are not smart enough not to understand, how big part of Canon's marketing this site is. In this day and age. 

Even tough a Canon user mostly, I've had many pleasant surprises with Sigma lenses. The need for reviewers to find con lists, is sometimes unbelievable. Seems to be linked either cause to another manufacturer or desperate need for YouTube attention. So how is it with the shoe?


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## Cali Capture (Apr 14, 2016)

Sounds like there is a bad case of caveat emptor ("buyer beware", For all you non Catholic school alums) against Dustin. Have the doubters "reviewed" his reviews, not just this or a few you may feel differ from your own opinion or more importantly "your priorities"? If you have you will find he follows the same format for all. Trying to bring forward negatives/cons is part of being objective and part of you weighing the impact those negatives may or may not have on how you use your gear. Same with the Plus points. To Imply that Dustin is sandbagging for Canon is truly unfair, and counter to every review I have seen/read from him. You could claim he was bias to Tamron, just because he one of the few that review Tamron's lenses. 
I think a lot of folks on this site forget that photography is an Art, using very scientific tools! Not the other way around. Those tools will be used in very different ways by different artists. A review should let us Know objectively what those elements of a tool are so we can determine our "own" value of that tool! Dustin is one of the best at always communicating all the aspects of lenses/gear!


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## verysimplejason (Apr 14, 2016)

AWR said:


> Let's be honest here. You, Canon Rumors, are very important part of Canon's marketing.
> 
> All the "insider tips", which no one else gets.
> Exclusive launch stories.
> ...



You might be mistaken if you think Dustin is like what you think he is. He's been using and endorsing some third party products like the Tamron 24-70 VC and oldies but goldies lenses. You can go to his site and read on a lot of his reviews including Zeiss lenses. 

Anyway, I've tried some sigma lenses starting from the 35 and they've got quite good optics. If only AF isn't one of their problems. I've got high hopes from this Sigma lens but its coma performance is really a turn off.


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## Cali Capture (Apr 14, 2016)

dilbert said:


> TWI by Dustin Abbott said:
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So you gotta ask why they don't spend the 10 cents! Same with Canon's "penny purse" lens bags. Why not just give use a better bag, or better sealing. If Canon can make a good bag for the 70-200mm f/2.8, why not the brand new 35mm II? Same for other mfg's. Sometimes the squeaky wheel has to wear down to the axel!


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## Luds34 (Apr 14, 2016)

dilbert said:


> TWI by Dustin Abbott said:
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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.


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## Random Orbits (Apr 14, 2016)

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. The size/heft of this lens is a disadvantage. This is a lens that you know you'll be using when you pack your bag rather than leaving in your bag all the time like the 35 f/2 IS.

It compares well against something like the Zeiss 21 from an IQ/price perspective. I gives you the option of using apertures as large as f/1.4. It is significantly sharper than the 24A in the center to midframe wide open, and the 24A is slightly better sharpness-wise compared to the 24L II wide open. I think it is intended to compete with the fast 24mm lenses, and people now have the choice of a bulbous but sharper 20A or a filterable 24.

The thing that is a disappoint is that they marketed this as an astro lens, and the coma results are disappointing in that light. Having to stop down to a minimum of f/2.8 to eliminate most of the coma suggests that astro was not a prime consideration for this lens design.

AF isn't as accurate as Canon, but that is to be expected. On my 5DIII, center AF accuracy is good, but it tends to front focus using the left and right cross banks at closer distances (about the same amount on the left and right side so it's not a decentering issue).


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## Luds34 (Apr 14, 2016)

Solid review as usual from Dustin.

I have to say, as an owner of the Voightlander 20mm, I really enjoyed the physical comparison with that lens. Really starts to put the Sigma Art lens into perspective.


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## Refurb7 (Apr 14, 2016)

jeffa4444 said:


> Its interesting to note the view on "weather sealing". Many professional lenses for cinematography which run many hundreds of thousands of $$$ more do not have weather sealing and nor do most motion picture cameras. They are used in hostile conditions and by & large with the exception of very fine dust remain OK because crew take precautions to protect the equipment.
> Any sensible photographer is not going to leave even weather sealed lenses or cameras out in the rain they are not completely weather proof and its not ideal operating wet equipment. Humidity doesnt respect weather sealing and fine dust is almost impossible to eliminate getting into a lens given lenses rack in & out or are exposed at the rear when dismounted from cameras.
> Weather sealing limits the effects of the environment but we should never assume it eliminates those effects.



I happen to do all of my stills photography without a crew. That's just the way that I roll. So weather sealing helps.


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## Refurb7 (Apr 14, 2016)

AWR said:


> That's right. This "review" is a really a cliche.
> In photography those "cons" will be overtaken by good photographer in a millisecond.
> I think this "review" has more to do with marketing Canon's new 16-35mm launch.



That comment is a total non sequitur. Totally disconnected from reality.


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## Refurb7 (Apr 14, 2016)

AWR said:


> Let's be honest here. You, Canon Rumors, are very important part of Canon's marketing.
> 
> All the "insider tips", which no one else gets.
> Exclusive launch stories.
> ...



You're not being "honest". Besides making no sense at all, you're being grossly unfair.


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## slclick (Apr 14, 2016)

AWR said:


> Let's be honest here. You, Canon Rumors, are very important part of Canon's marketing.
> 
> All the "insider tips", which no one else gets.
> Exclusive launch stories.
> ...



I doubt Canon, Inc gives a rats aperture about this site. Dustin is a huge 3rd party supporter and even a quick visit to his site proves that. Way off base imho.


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## Stephen Melvin (Apr 14, 2016)

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.


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## ahsanford (Apr 14, 2016)

AWR said:


> That's right. This "review" is a really a cliche.
> In photography those "cons" will be overtaken by good photographer in a millisecond.
> I think this "review" has more to do with marketing Canon's new 16-35mm launch.



Dustin Abbott = 2000+ posts at this site, including a host of many valuable reviews -- often speaking glowingly of 3rd party lenses.

He answers questions here in this forum and candidly pegs strengths and weaknesses of gear. I can say from my experience of having read more than 10 of his reviews that he's as pro-Canon as DXO is. 

- A


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## j-nord (Apr 14, 2016)

As soon as I saw the announcement for this lens, it caught my attention as a potential astro lens. Poor coma control is a mistake, a lot of potential buyers in this market. I'd prefer a more versatile AF lens that can double as an astro lens over getting manual focus Rokinon lenses. Also 20mm is quite a bit better than 24mm for astro landscapes.


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## jeffa4444 (Apr 14, 2016)

dilbert said:


> TWI by Dustin Abbott said:
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To Dustin / Canon defence of this proper weather sealing is not "a few cents" its much more complex than that and involves machined parts being adapted for seals, more careful assembly with tighter tolerances and materials that will not decompose or rot in harsh environments. Seals to switches and buttons are not easy to design or impliment I know Ive had experiance of this in building equipment. 

Lenses are almost impossible to completely seal because even internal focusing assemblies move to acheive focus or zoom which displaces air and therefor cannot be in a vaccuum but they then can induce suction which will move dust.


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## jeffa4444 (Apr 14, 2016)

TWI by Dustin Abbott said:


> jeffa4444 said:
> 
> 
> > Its interesting to note the view on "weather sealing". Many professional lenses for cinematography which run many hundreds of thousands of $$$ more do not have weather sealing and nor do most motion picture cameras. They are used in hostile conditions and by & large with the exception of very fine dust remain OK because crew take precautions to protect the equipment.
> ...


I agree people want weather sealing however some dont fully understand what were actually getting is measures to help avoid ingres or limit ingres not eliminate it. 

On your second point I also agree my own experiance with the Canon 6D has been positive having been caught out twice in sudden summer storms in remote areas of Dartmoor where the camera got a soaking but lived to tell the tale without incident. Being prepared to dry it does help however, I always carry cloths.


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## jeffa4444 (Apr 14, 2016)

dilbert said:


> Luds34 said:
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Having handled both Blackstone.


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## TWI by Dustin Abbott (Apr 14, 2016)

A lively discussion is good. My experience says that I am most likely to experience "lively discussion" when I review Sigma lenses for some reason.


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## Larsskv (Apr 14, 2016)

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.


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## Andyx01 (Apr 14, 2016)

Luds34 said:


> dilbert said:
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> > TWI by Dustin Abbott said:
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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.


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## ahsanford (Apr 14, 2016)

Larsskv said:


> Random Orbits said:
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> > 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.
> ...



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


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## slclick (Apr 14, 2016)

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.


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## Larsskv (Apr 14, 2016)

ahsanford said:


> Larsskv said:
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That will be very interesting to see. I was under the impression that the BR element was for removing chromatic aberrations. It would be amazing if it affects coma to.


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## ahsanford (Apr 14, 2016)

Larsskv said:


> That will be very interesting to see. I was under the impression that the BR element was for removing chromatic aberrations. It would be amazing if it affects coma to.



Fair comment. The 35L II is far more than 'just the 35L I with BR gunk added' -- it's a new optical design. It's quite possible that the BR stuff is not the source of the coma improvement.

- A


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## pierlux (Apr 14, 2016)

slclick said:


> AWR said:
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> > Let's be honest here. You, Canon Rumors, are very important part of Canon's marketing.
> ...



This. I was about to reply more or less the same except replacing "I doubt" with "I'm certain".

@ Dustin: I'd love a review of the Venus Optics - Laowa 15mm f/4 ultrawide 1:1 Macro/shift lens, it intrigues me so much. It's so... unique one would even overlook a poor optical performance. If only it costed a bit less... Sorry for the OT, talking about 3rd party lenses I just happened to think of it.


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## Larsskv (Apr 14, 2016)

slclick said:


> Stephen Melvin said:
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> 
> > 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.
> ...



From my experience so far, I find the AF on the 20A to be very acceptable on my 5Ds.


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## JohnDizzo15 (Apr 14, 2016)

Coma control is actually pretty good on the lens and is competitive with most everything else on the market (as simple as doing a google search to find test results). At f2, it is performing really well already. So I don't consider this a knock on the lens itself. It may not be perfect with regard to coma, but no one else is either especially when you consider that there is no other direct competitor. So to that, I say, one should try to compare the Sigma coma performance to the other brands of 20mm f/1.4 lenses. 

The better way to look at this lens would be to see it as a unique piece that gives you the ability to shoot in new and different ways than you could before with anything else. Prior to this, anything you had in this focal range would max out at 2.8 so the Sigma stands alone here.

With regard to AF, this thing is wide enough (with a much larger on average DOF) that it probably isn't anywhere near as much of an issue when compared with the 35 and 50 Art. I personally use all of these adapted to an A7R2 so I cannot comment on how well the 20 would perform on a DSLR at this point.

Lack of weather seal is a legitimate con for the lens for those that need it. Doesn't matter for my uses though. 

Incompatibility with filters is also legitimately a big issue for many that would be interested in a lens of this type. Again, not an issue for me though as I use it mostly as a walk around.

With regard to the knock on Dustin... He's always been a stand up guy and his reviews have always been thoroughly legit. The knock is a fairly unfair assessment as he is one of the more respectable dudes around the net. In the words of the great Joe Dirt, "Keep on keepin' on," Dustin.


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## blanddragon (Apr 14, 2016)

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).


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## slclick (Apr 14, 2016)

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.


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## Random Orbits (Apr 14, 2016)

Larsskv said:


> Random Orbits said:
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> > 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.
> ...



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.
_


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## ahsanford (Apr 14, 2016)

JohnDizzo15 said:


> With regard to the knock on Dustin... He's always been a stand up guy and his reviews have always been thoroughly legit. The knock is a fairly unfair assessment as he is one of the more respectable dudes around the net. In the words of the great Joe Dirt, "Keep on keepin' on," Dustin.



+1. One snap-judgment poster throwing haymakers at (of all people) Dustin for having a Canon bias is pretty laughable.

I have to chalk that one up to ignorance -- just open a few reviews at his site and it won't take long to see what a thorough and fair reviewer he is.

- A


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## 9VIII (Apr 14, 2016)

I might get a Sigma 20mm if the Quattro H comes in at a reasonable price, but as an APS-C user this lens is made completely redundant by the 18-35A, which is cheaper and basically the same in terms of IQ and light gathering (18-35A has a transmission value of T1.8, same as the aperture, where f1.4 lenses usually come out closer to T1.6 for light transmission, theoretically it's nearly a wash between the two. You just can't produce the same Bokeh with a smaller aperture).


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## JohnDizzo15 (Apr 14, 2016)

Random Orbits said:


> Larsskv said:
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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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## Random Orbits (Apr 14, 2016)

ahsanford said:


> Larsskv said:
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+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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## ahsanford (Apr 14, 2016)

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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## ahsanford (Apr 14, 2016)

slclick said:


> blanddragon said:
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> 
> > 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).
> ...



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! 

- A


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## Random Orbits (Apr 14, 2016)

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.
> ...



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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## infared (Apr 14, 2016)

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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## ahsanford (Apr 14, 2016)

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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## slclick (Apr 14, 2016)

ahsanford said:


> slclick said:
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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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## StudentOfLight (Apr 14, 2016)

Wow, with some of these comments I rolled my eyes so hard I dislocated my eyeballs.

Keep up the good work Dustin, I always find value in your reviews.


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## Stephen Melvin (Apr 14, 2016)

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.
> ...



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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## JohnDizzo15 (Apr 14, 2016)

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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## ahsanford (Apr 14, 2016)

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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## JohnDizzo15 (Apr 14, 2016)

ahsanford said:


> JohnDizzo15 said:
> 
> 
> > That might have been true before the Tamron 15-30.
> ...


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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## jhpeterson (Apr 14, 2016)

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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## Luds34 (Apr 15, 2016)

Andyx01 said:


> Luds34 said:
> 
> 
> > dilbert said:
> ...



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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## Maximilian (Apr 15, 2016)

dilbert said:


> Luds34 said:
> 
> 
> > ...
> ...


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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## Maximilian (Apr 15, 2016)

dilbert said:


> Maximilian said:
> 
> 
> > ...
> ...


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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## Larsskv (Apr 15, 2016)

dilbert said:


> Maximilian said:
> 
> 
> > ...
> ...



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 (Apr 15, 2016)

WOW! I Thought that the topic was the incredible new Sigma 20mm f/1.4?????? ???


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## jabbott (Apr 15, 2016)

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!
> ...


+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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## Luds34 (Apr 15, 2016)

dilbert said:


> Luds34 said:
> 
> 
> > ...
> ...



I think you might want to work on your sarcasm detection.


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## JohnDizzo15 (Apr 15, 2016)

jabbott said:


> infared said:
> 
> 
> > One of my most favorite lenses EVER!
> ...



Yup and yup. I have a special place in my heart for lenses that give me very unique looks and/or the ability to do something new that I couldn't before. What is also odd/great about the lens is that you still get plenty of subject isolation/separation for environmental portraits. Considering the differences in amount of DOF on such a wide FL vs something between 35-50, it is definitely surprising that you can still get that amount of isolation.


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## j-nord (Apr 16, 2016)

Today I learned the most important aspect to a lens or body is weather sealing. If it isnt the best of the best, its useless crap.


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## dufflover (Apr 18, 2016)

Weather sealing as a marketing term is one of the biggest load of crocks ever. Sure it exists, and exists to different levels, but the number of people who _think_ they need it cos a few drops of rain fell is hilarious. Or they blame a badly built camera because _they_ dropped it from a height :


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