# Sigma Launches 20mm f/1.4 DG HSM Art



## Canon Rumors Guy (Oct 16, 2015)

```
Truly wide and truly fast, the Canon EF mount 20mm f/1.4 DG HSM Lens is a member of the venerable Art series of Global Vision lenses from Sigma and pairs a sophisticated optical design with a robust physical construction. Comprised of 15 elements in 11 groups, the lens design includes both “F” Low Dispersion (FLD) and Special Low Dispersion (SLD) glass to significantly reduce chromatic and spherical aberrations, as well as limit distortion for clean, sharp, and evenly illuminated imagery. A Super Multi-Layer Coating has also been applied to minimize surface reflections, flare, and ghosting for increased contrast and color accuracy. The wide focal length and consistent image quality make this lens especially suitable for landscape, interior, architectural, and astrophotography applications, while the fast f/1.4 maximum aperture deems it ideal for natural and low-light shooting.</p>
<p><!--more--></p>
<p>Complementing the optical performance is an equally adept Hyper Sonic Motor, which provides fast, smooth, and near-silent autofocus performance. This focusing motor also enables full-time manual focus override at any time just by rotating the focus ring for refined manual control and focusing as close as 10.9″. The lens barrel is constructed using a Thermally Stable Composite material, which supports working in a wide variety of temperatures and conditions, and the lens mount is constructed from brass for long-term durability and mounting accuracy. Additionally, this lens is also compatible with the optional Sigma USB Dock for fine-tuned control over focusing parameters and other lens characteristics.</p>
<ul>
<li>As part of the Art line within Sigma’s Global Vision series, this lens’ is designed to achieve truly notable optical performance and is ideally suited for creative and artistic applications.</li>
<li>Prime wide-angle 20mm f/1.4 lens is designed for full-frame format Canon EF mount DSLRs, and can also be used with APS-C models where it will provide a 32mm equivalent focal length.</li>
<li>Fast f/1.4 maximum aperture is well-suited for working in low-light conditions and also provides greater control over the focus position when using shallow depth of field techniques.</li>
<li>Both FLD glass and five SLD elements have been incorporated within the lens design to correct for chromatic aberrations throughout the entire focusing range and help to ensure high image sharpness, clarity, and contrast regardless of focus point or aperture setting.</li>
<li>A Super Multi-Layer Coating has been applied to lens elements in order to minimize lens flare and ghosting and contribute to producing contrast-rich and color-neutral imagery, even in backlit conditions.</li>
<li>The integrated HSM (Hyper Sonic Motor) realizes quick and quiet autofocusing, which is further complemented by an optimized AF algorithm to produce smoother focusing performance. The HSM also permits full-time manual focus control simply by rotating the focus ring at any time.</li>
<li>A rounded nine-blade diaphragm helps to produce an attractive out-of-focus quality.</li>
<li>Petal-shaped lens hood helps to reduce lens flare when working in strong lighting conditions and also offers some protection to the front element of the lens.</li>
<li>The lens is constructed using a Thermally Stable Composite (TSC) material, along with traditional metals, for greater precision and use in wide temperature variations.</li>
<li>The bayonet mount is constructed from brass for ensured accuracy and durability.</li>
<li>This lens is compatible with the optional Sigma USB Dock for fine-tuning different lens characteristics and updating its firmware.</li>
</ul>
<p><strong>Preorder Sigma 20mm f/1.4 DG HSM Art $899: <a href="http://www.bhphotovideo.com/c/product/1191178-REG/sigma_20mm_f_1_4_art_lens.html/bi/2466/kbid/3296" target="_blank">B&H Photo</a></strong></p>
```


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## d (Oct 16, 2015)

Very interested in seeing a few sample images from this lens, especially in from an astrophotographic point of view. Price seems incredibly reasonable as well. This could be the one I've been waiting for!

d.


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## infared (Oct 16, 2015)

What a great surprise this lens is....Let's see some sample images and a good review !!! I can't wait. 
WOW! it can be preordered at B&H and is $120 cheaper than I expected.....: Oh MY!


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## baervan (Oct 16, 2015)

Looks good but aw man, why cant i get a lens that i need.. 

this shouldve been a ultra wide, 16mm at least or... a friggin 85mm! 

i'll keep on waitin'


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## Coldhands (Oct 16, 2015)

If they manage to keep the coma and light falloff under control, this may end up being my first ever third-party lens purchase. Sounds like the ideal wide-field astro lens (on paper).


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## Chaitanya (Oct 16, 2015)

Where are the Art Macro lenses?


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## DLD (Oct 16, 2015)

Anybody have a clue as to the filter size? I figure 77mm isn't totally out of the question however the design could lead to softer/darker corners wide open I assume it's the new 82mm standard?


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## Viggo (Oct 16, 2015)

DLD said:


> Anybody have a clue as to the filter size? I figure 77mm isn't totally out of the question however the design could lead to softer/darker corners wide open I assume it's the new 82mm standard?



No filters with bulbous front element.


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## jcarapet (Oct 16, 2015)

Don't need, but sure as heck want. I have been thinking about a low light astrophotography lens for a while so this could be the one. Can't justify spending $900 for just that, but still....


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## jthomson (Oct 16, 2015)

Chaitanya said:


> Where are the Art Macro lenses?



The Sigma 150mm and 180mm macro lenses were updated just before sigma switched to its Global Vision nomenclature. They are both excellent lenses.


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## infared (Oct 16, 2015)

baervan said:


> Looks good but aw man, why cant i get a lens that i need..
> 
> this shouldve been a ultra wide, 16mm at least or... a friggin 85mm!
> 
> i'll keep on waitin'



20mm is my sweet spot...dynamic but not TOO wide!


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## infared (Oct 16, 2015)

DLD said:


> Anybody have a clue as to the filter size? I figure 77mm isn't totally out of the question however the design could lead to softer/darker corners wide open I assume it's the new 82mm standard?


I am thinking that there is no filter thread. The fact that it is a highly-corrected (hopefully) f/1.4...I think that we have a round, bulbous front end. That looks like a fixed hood and B&H usually has all specs when listing an item, but their site says: "Filter Size- Specs not listed by manufacturer". So I am betting it will need an over-the-hood filter holder....which is REALLY unusual for a 20mm lens..but this is an unusual 20mm that is pushing the limits.
Right?


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## verysimplejason (Oct 16, 2015)

If coma is good and it is sharp enough, this will be my go-to wide lens.


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## epsiloneri (Oct 16, 2015)

Yes, fixed hood and no filter threads. There is a lot more info on SiGMA's webpages. 2.3 stops of corner vignetting doesn't sound too bad. The wide-open MTF charts don't look too impressive (not much to compare to) but the coma performance will be decisive for me (as for many others). The other ARTs have been a bit of a disappointment in this regard, so I really hope this one holds up.


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## slclick (Oct 16, 2015)

It's always $899 isn't it


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## Alex_M (Oct 16, 2015)

http://www.sigma-global.com/en/lenses/cas/product/art/a_20_14/features.html

http://www.sigma-global.com/en/lenses/cas/product/art/a_24_14/features.html

Spend an hour comparing these two pages side by side: mtf charts, vingetting, optical construction formula, distortion chart. 

To me, according to provided charts on these pages, the performance of the new 20/1.4 Art is almost identical to 24/1.4 Art. MTF charts are so close that I had to open both of these pages side by side to spot the differences. 

The major difference in the bulging large double aspherical front element on the 20/1.4 Art. Will that front element make all the difference in the coma department remains to be seen.


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## rfdesigner (Oct 16, 2015)

epsiloneri said:


> Yes, fixed hood and no filter threads. There is a lot more info on SiGMA's webpages. 2.3 stops of corner vignetting doesn't sound too bad. The wide-open MTF charts don't look too impressive (not much to compare to) but the coma performance will be decisive for me (as for many others). The other ARTs have been a bit of a disappointment in this regard, so I really hope this one holds up.



Well, lets compare this to canons nearest, the 24f1.4L







and here's the sigma






take the black lines on the 24 vs the red and green on the 20


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## BeenThere (Oct 16, 2015)

Alex_M said:


> http://www.sigma-global.com/en/lenses/cas/product/art/a_20_14/features.html
> 
> http://www.sigma-global.com/en/lenses/cas/product/art/a_24_14/features.html
> 
> ...


Yes, I suspect that like the 24mm Art lens, decent coma by f/2.8. But that isn't a terrible outcome because vignette is much better at f/2.8, so still a little better than 2.8 rivals for astro. Just guessing, but getting decent coma at f/1.4 would seem to be beyond state of the art.


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## Alex_M (Oct 16, 2015)

Apparently, Dual Aspherical front element can and should improve situation with coma. There is a hope!

http://www.mir.com.my/rb/photography/opinion/html/aspherical.htm

"... Fast lenses, at times has problem maintaining its optical performance at widest opening, especially in situation where the illumination is dim. A aspherical lens can assure optimum correction of coma. Like images of scenes with small points of light - bright point sources of light near the edges of the picture appear as dots rather than comet-shaped blurs. Some newer generation of fast lens, like the world's fastest 28mm lens, the AF Nikkor 28mm f/1.4D, or the recent Canon's super fast EF 50mm f1.0 L use an aspherical element to ensure compact size and to obtain superb performance by eliminating sagittal, or arrow shaped, coma, even at its widest aperture...."


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## infared (Oct 16, 2015)

epsiloneri said:


> Yes, fixed hood and no filter threads. There is a lot more info on SiGMA's webpages. 2.3 stops of corner vignetting doesn't sound too bad. The wide-open MTF charts don't look too impressive (not much to compare to) but the coma performance will be decisive for me (as for many others). The other ARTs have been a bit of a disappointment in this regard, so I really hope this one holds up.



Oh...DUH! LOL!....thanks for the link...there is a lot more info at the Sigma page than there is in the press release....That link should be at the top of this page with the post. ;D


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## ahsanford (Oct 16, 2015)

infared said:


> DLD said:
> 
> 
> > Anybody have a clue as to the filter size? I figure 77mm isn't totally out of the question however the design could lead to softer/darker corners wide open I assume it's the new 82mm standard?
> ...



Hood is permanent + front element is bulbous = no filter threads possible. Hand hold your filters, wait for Lee / Wonderpana bulbous lens outrigger support, or _find another lens_. 

IMHO, daylight landscapers should avoid this lens for now. If it turns out to a be a beast optically, if a front-filtering option eventually appears, etc. then it might be a fine choice.

But let's face it, with no front filtering, this 20mm prime I believe is aimed squarely at astro people. Perhaps also at events where flash is prohibited (like a concert).

- A


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## epsiloneri (Oct 16, 2015)

Alex_M said:


> Apparently, Dual Aspherical front element can and should improve situation with coma. There is a hope!


Nice! But..:


> the *recent* Canon's super fast *EF 50mm f1.0 L* use an aspherical element


...it was introduced in 1989 and discontinued 15 years ago


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## Chaitanya (Oct 16, 2015)

jthomson said:


> Chaitanya said:
> 
> 
> > Where are the Art Macro lenses?
> ...


I know Sigma updated their 105/150/180mm lenses just before the launch of global visions lineup. Although I would have liked to Sigma update those lenses with Art nomenclature to how Sigma had updated their 120-300mm f/2.8 to Sport lens via an electronic circuit update. Just few months back I use the Sigma 180mm macro for snakes and I really like the lens. Having ability to upgrade the firmware to improve compatibility of lens at home is much better than having to send it service centre or having no update at all and keep getting Err99.


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## Jesse (Oct 16, 2015)

Doesn't Sigma want more of MY money? Gimme a damn 85 already!


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## NancyP (Oct 16, 2015)

Yes, I would (and do) use a 180mm lens for close-ups of pit vipers. ;D With 1.4x teleconverter on, just for a little more distance from a temperamental cottonmouth (grumpiest regional pit viper). When one displays (gapes, showing white mouth lining), I back up! Speaking of which, there may be a shortage of anti-venin soon, the small company that inoculates the large animals (horses, I believe) may be going out of business due to retirement. Some molecular biologists are working on developing a recombinant "humanized" anti-venin antibody , which would be good - probably less expensive in the long run, fewer side effects.


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## ahsanford (Oct 16, 2015)

Jesse said:


> Doesn't Sigma want more of MY money? Gimme a damn 85 already!



If I had to rank the priority of need for primes (for all photographers, not just for my needs), I would guess:

1) 50*
2) 85
3) 35*
4) 100/Macro
5) 135
6) 24*
7) A prime in the 14 - 20 range*
8 ) 200

* = Art prime released/announced

So Sigma's March of the Art Primes seems an interesting battle plan to say the least. It's possible that they've just cherry picked weaker Canon lenses to outperform (the 35L and 50L are spectacularly low hanging fruit from a resolution perspective) or wanted to nail gaps that no one offers (like this 20mm Art), but eventually they need to go toe-to-toe with Canon and Nikon's best primes.

We shall see what's next, but we'd be foolish to not expect an 85mm Art before much longer.

- A


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## sleepnever (Oct 16, 2015)

I love my Sigma 50 f/1.4 A (event though I had to get a 2nd copy), but man I wish it was weather sealed. Ok, maybe not the 50, but I can't believe they made a wide-angle 20 f/1.4 that sky/astrophotogs will love, but didn't weather seal it. Come on Sigma!!!


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## ahsanford (Oct 16, 2015)

sleepnever said:


> I love my Sigma 50 f/1.4 A (event though I had to get a 2nd copy), but man I wish it was weather sealed. Ok, maybe not the 50, but I can't believe they made a wide-angle 20 f/1.4 that sky/astrophotogs will love, but didn't weather seal it. Come on Sigma!!!



It's like Sigma is saying:
_
"Many have noted that this lens is not weather-sealed. This is not a problem because -- as we all know -- astrophotography should not be performed in the rain."
_
- A


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## epsiloneri (Oct 16, 2015)

ahsanford said:


> It's like Sigma is saying:
> _"Many have noted that this lens is not weather-sealed. This is not a problem because -- as we all know -- astrophotography should not be performed in the rain."_


But then AF would be superfluous as well! Perhaps that's why they go 20 rather than 85 - temperamental AF not as much of an issue.


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## sleepnever (Oct 16, 2015)

ahsanford said:


> sleepnever said:
> 
> 
> > I love my Sigma 50 f/1.4 A (event though I had to get a 2nd copy), but man I wish it was weather sealed. Ok, maybe not the 50, but I can't believe they made a wide-angle 20 f/1.4 that sky/astrophotogs will love, but didn't weather seal it. Come on Sigma!!!
> ...



Well even for me as a Landscape photographer... being out at night, in the cold, or somewhere where it is wet (PacNW for example), weather sealed lenses are handy. That was my point.


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## ahsanford (Oct 16, 2015)

sleepnever said:


> ahsanford said:
> 
> 
> > sleepnever said:
> ...



I hear you. Just wisecracking on my part. 

Unlike a black/white feature like IS -- where you simply have it or you don't -- sealing isn't so binary. There are a thousand shades of weather protection, and in absence of an industry standard, I don't trust any manufacturer's statements on it. 

I'd use a Sigma Art in the rain, but I wouldn't leave it out in a downpour. Same is true of my sealed L lenses.

- A


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## erjlphoto (Oct 16, 2015)

infared said:


> What a great surprise this lens is....Let's see some sample images and a good review !!! I can't wait.
> WOW! it can be preordered at B&H and is $120 cheaper than I expected.....: Oh MY!



Thanks for the heads up! I checked out the price and am floored at how reasonable it is. Makes more sense As an addition to my Canon 24-70 than a wide angle f/4 zoom....


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## ahsanford (Oct 16, 2015)

erjlphoto said:


> infared said:
> 
> 
> > What a great surprise this lens is....Let's see some sample images and a good review !!! I can't wait.
> ...



_...unless you are principally shooting landscapes_. Even at $150 more, I'd get the 16-35 f/4L IS *ten times out of ten* over this Art lens if so. Consider, the 16-35 F/4L IS has a number of huge upsides:


Front filter ring, at the ubiquitous 77mm to boot (jillions of options there)
If you need ND grads, 4x6 filters, etc, you can do it with the Lee 100mm system (again, jillions of filter options) instead of some complicated expensive options like Lee SW150 or the Wonderpana system
Far lighter
Weather sealed
Shoots down to 16mm FOV -- sometimes you _can't_ move your feet with landscape work...

I'll leave sharpness out (we don't know yet) and IS as in low light handheld work it's likely a wash with a three stop faster lens.

I don't want to talk you out of what might be a great new lens with this Sigma, but I'd consider the above before you make a buying decision. Again, it all depends on what you shoot.

- A


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## Chaitanya (Oct 17, 2015)

NancyP said:


> Yes, I would (and do) use a 180mm lens for close-ups of pit vipers. ;D With 1.4x teleconverter on, just for a little more distance from a temperamental cottonmouth (grumpiest regional pit viper). When one displays (gapes, showing white mouth lining), I back up! Speaking of which, there may be a shortage of anti-venin soon, the small company that inoculates the large animals (horses, I believe) may be going out of business due to retirement. Some molecular biologists are working on developing a recombinant "humanized" anti-venin antibody , which would be good - probably less expensive in the long run, fewer side effects.



I usually use the 100mm f/2.8 L for photographing snakes(both venomous and non venomous), on this occasion my 100mm failed so I had to borrow the 180mm lens from a friend of mine. If you ever visit western part of India, please do let me know I will show you the Russell's viper these guys have worse temperament than any other vipers I have seem to this day. Even I help with research projects related to snake venom and producing better Anti venom. India is already facing a shortage of quality Anti venom, the reasons here are lack of political will power and animal rights activists shutting down couple of antivenom production units.


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## Berowne (Oct 17, 2015)

The only comparable lens is the Leica Summilux-M 21/1.4 Asph. Price is slightly higher. It comes with less elements and the front group is similar. Does anyone has a legend für the MTF Charts of the Sigma (how many lines per mm is the red and green graph? I guess 5 and 10.) 

http://en.leica-camera.com/Photography/Leica-M/M-Lenses/SUMMILUX-M-21mm-f-1.4-ASPH/Downloads


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## Talley (Oct 17, 2015)

Berowne said:


> The only comparable lens is the Leica Summilux-M 21/1.4 Asph. Price is slightly higher. It comes with less elements and the front group is similar. Does anyone has a legend für the MTF Charts of the Sigma (how many lines per mm is the red and green graph? I guess 5 and 10.)
> 
> http://en.leica-camera.com/Photography/Leica-M/M-Lenses/SUMMILUX-M-21mm-f-1.4-ASPH/Downloads



Still it's 21mm... which I know it means not alot but it's still not 20. And I have suspicions that this Sigma will be ART quality.


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## hiepphotog (Oct 17, 2015)

Berowne said:


> The only comparable lens is the Leica Summilux-M 21/1.4 Asph. Price is slightly higher. It comes with less elements and the front group is similar. Does anyone has a legend für the MTF Charts of the Sigma (how many lines per mm is the red and green graph? I guess 5 and 10.)
> 
> http://en.leica-camera.com/Photography/Leica-M/M-Lenses/SUMMILUX-M-21mm-f-1.4-ASPH/Downloads



I don't think anyone would publish a 5 and 10 only MTF chart. Sigma's chart is 10 and 30. The Lux 21's price is not slightly higher; it's $7k. It's also abysmal at coma control. Of course, its redeeming quality is being smaller and lighter.


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## DLD (Oct 17, 2015)

Viggo said:


> DLD said:
> 
> 
> > Anybody have a clue as to the filter size? I figure 77mm isn't totally out of the question however the design could lead to softer/darker corners wide open I assume it's the new 82mm standard?
> ...


At 20mm. That's kind of disappointing. However I do shoot astro stuff, using a 14mm Samyang for that right now. Which isn't easy to get good filters for... I've had my eye on the 15-30mm Tamron but the filter issue is still there... This Sigma may be good but I feel somewhat limited without any viable filter option... however 1.4 at 20mm...


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## freezehead (Oct 18, 2015)

DLD said:


> Viggo said:
> 
> 
> > DLD said:
> ...



For Tamron 15-30 or Sam 14mm, you can use the fotodiox filter system, look for dustin abbot review, they are ~500$


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## infared (Oct 18, 2015)

Has anyone found any images posted on the web that were shot with this lens?????
Surprisingly, not even Sigma has posted any images yet on their own product page.


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## Berowne (Oct 18, 2015)

hiepphotog said:


> Berowne said:
> 
> 
> > The only comparable lens is the Leica Summilux-M 21/1.4 Asph. Price is slightly higher. It comes with less elements and the front group is similar. Does anyone has a legend für the MTF Charts of the Sigma (how many lines per mm is the red and green graph? I guess 5 and 10.)
> ...



Is the chart calculated or measured, wich is the saggital and wich the tangential (analog to the Canon chart?). Is red and green 10 and 30l/mm or shut down and wide open?


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## 100 (Oct 18, 2015)

Berowne said:


> hiepphotog said:
> 
> 
> > Berowne said:
> ...



Sigma has a MTF chart guide on their website: 
http://www.sigma-global.com/en/lenses/cas/product/art/a_20_14/data.html


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## Rudeofus (Oct 18, 2015)

Berowne said:


> The only comparable lens is the Leica Summilux-M 21/1.4 Asph.



A Leica M lens doesn't have to jump through hoops to accommodate a mirror, which is a huge advantage in the wide angle domain. If the Leica isn't significantly better in all regards than the Sigma, Leica did something seriously wrong. These two are not similar lenses from a design stand point, even if their focus length and max aperture are close.


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## hiepphotog (Oct 18, 2015)

Rudeofus said:


> Berowne said:
> 
> 
> > The only comparable lens is the Leica Summilux-M 21/1.4 Asph.
> ...



Unfortunately, I doubt the Leica would be even better, let alone significantly better. The only things better are size/weight and filter acceptability. As a fan/user of small lightweight lenses, this Sigma might be the only exception (if coma control is good).


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## PhotographyFirst (Oct 18, 2015)

Rudeofus said:


> Berowne said:
> 
> 
> > The only comparable lens is the Leica Summilux-M 21/1.4 Asph.
> ...



Doesn't the flange distance on the Leica pose a huge issue for the corners of the image when shot wide open? The Sigma obviously has a much greater flange distance and might do much better than the Leica. Leica cameras have to do a lot of digital corrections to make their wide and fast lenses work at all. They couldn't be beat in the film days, but with digital, the design of the flange distance and lenses is all wrong.


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## Talley (Oct 25, 2015)

According to their own MTF charts this 20mm performs just slightly better than the 24mm ART.

I have the 24/35/50 arts and they are all amazing wide open. 

I do belive this 20 will be on my purchase list.


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## BeenThere (Oct 31, 2015)

Lenstip has some sample jpegs from the new Sigma 20mm. F/1.4 looks pretty good at the frame edges. Nothing there to evaluate or hint at coma performance.
http://www.lenstip.com/2162-news-Sigma_A_20_mm_f_1.4_DG_HSM_-_sample_images.html


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## Chapman Baxter (Nov 1, 2015)

BeenThere said:


> Lenstip has some sample jpegs from the new Sigma 20mm. F/1.4 looks pretty good at the frame edges. Nothing there to evaluate or hint at coma performance.
> http://www.lenstip.com/2162-news-Sigma_A_20_mm_f_1.4_DG_HSM_-_sample_images.html



Those shots of the buildings at f/1.4 look dreadfully soft and hazy to me, even in the centre. If it's representative of the lens and not just a bad copy or bad focusing, I'd find it very disappointing.


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## Djaaf (Nov 3, 2015)

Lenstip just posted its review of the Sigma : http://www.lenstip.com/457.1-Lens_review-Sigma_A_20_mm_f_1.4_DG_HSM_Introduction.html

Pretty much the same results as the 24 f/1.4 : very good optics, except for the %$##%$ coma. 

Damn... maybe next time... :'( 


Djaaf.


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## Random Orbits (Nov 5, 2015)

Djaaf said:


> Lenstip just posted its review of the Sigma : http://www.lenstip.com/457.1-Lens_review-Sigma_A_20_mm_f_1.4_DG_HSM_Introduction.html
> 
> Pretty much the same results as the 24 f/1.4 : very good optics, except for the %$##%$ coma.
> 
> ...



+1. This is disappointed, especially after its launch announcement contained

_The wide focal length and consistent image quality make this lens especially suitable for landscape, interior, architectural, and astrophotography applications, while the fast f/1.4 maximum aperture deems it ideal for natural and low-light shooting._

Why claim that its suitable for astrophotography applications if can't use it wide open?


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## PhotographyFirst (Nov 5, 2015)

Djaaf said:


> Lenstip just posted its review of the Sigma : http://www.lenstip.com/457.1-Lens_review-Sigma_A_20_mm_f_1.4_DG_HSM_Introduction.html
> 
> Pretty much the same results as the 24 f/1.4 : very good optics, except for the %$##%$ coma.
> 
> ...



Well that sure is a kick in the nuts. They just lost a godnumber of sales right off the bat with that horrid coma. 

They will still sell plenty of them to the party-wagon Art primes buyers though. I've come across many people in other forums who buy the art primes because they are "awesome" without much thought about how they are actually going to put them into use.


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## ahsanford (Nov 5, 2015)

PhotographyFirst said:


> Djaaf said:
> 
> 
> > Lenstip just posted its review of the Sigma : http://www.lenstip.com/457.1-Lens_review-Sigma_A_20_mm_f_1.4_DG_HSM_Introduction.html
> ...



Agree, the coma results take away the homerun astro lens possibility, but this lens will sell as much for its unique niche as it will being 'another Art prime'. _Nothing else this sharp, wide and fast exists with AF._ I could see this used for reportage, concerts, events, etc.

Also, those who own the EF 11-24mm f/4 zoom EF 11mm f/4 prime -- i.e. those with U-UWA sickness -- might want a portrait lens for their needs. 

- A


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## PhotographyFirst (Nov 5, 2015)

ahsanford said:


> PhotographyFirst said:
> 
> 
> > Djaaf said:
> ...



LoL. Good point.


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## PVS (Nov 7, 2015)

It's hard to believe people are actually complaining and being disappointed by this lens in this thread. If the real samples are anything up to LensTip results then we have a really unique UWA lens here. Disappointing - compared to what!? Seriously.


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## ahsanford (Nov 7, 2015)

PVS said:


> It's hard to believe people are actually complaining and being disappointed by this lens in this thread. If the real samples are anything up to LensTip results then we have a really unique UWA lens here. Disappointing - compared to what!? Seriously.



A solid half of the enthusiasm in this lens was for astro. One corner coma shot wide open effectively put that usage to the sword. Hence, people are bummed.

I still think it's a fine and unique option for many other applications, but for the ever-so-demanding astro crowd, this is more of a miss than a hit.

- A


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## PVS (Nov 7, 2015)

I'm aware of that it's just that no one seems to get it how hard it is to design lens like this anyway, not many 21mm lenses on the market and even less with aperture faster than f/2.8 and, frankly, among those 2.8 21mils there very few of the ones with acceptable performance wide open.

Astro bandwagon is just a small portion of the market this lens hits right in the center. We should all be excited. 

I had the old 24/1.8 Smegma and even though it was not a great lens I was very happy with what I got with that lens mounted on 5Dc I used to have. Not immaculate all over the frame when printed more than 12'' on the longer side but still much much better what I could get with anything else before. 

Samples:



The Three Kings by OverdeaR [donkey&#x27;s talking monkey&#x27;s nodding], on Flickr



Milky Way by OverdeaR [donkey&#x27;s talking monkey&#x27;s nodding], on Flickr



Milky Way Galaxy by OverdeaR [donkey&#x27;s talking monkey&#x27;s nodding], on Flickr

Heck, even the old 20/1.8 which borrowed on few occasions could get you in the area no gear had before: 



vertical / stars / wood / rock by OverdeaR [donkey&#x27;s talking monkey&#x27;s nodding], on Flickr


Things are only getting miles better yet nobody's happy. Strange days.


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## PhotographyFirst (Nov 7, 2015)

PVS said:


> I'm aware of that it's just that no one seems to get it how hard it is to design lens like this anyway, not many 21mm lenses on the market and even less with aperture faster than f/2.8 and, frankly, among those 2.8 21mils there very few of the ones with acceptable performance wide open.
> 
> Astro bandwagon is just a small portion of the market this lens hits right in the center. We should all be excited.
> 
> Things are only getting miles better yet nobody's happy. Strange days.



If the coma was even decent, I would agree that it would be a great lens, even if coma wasn't perfect. The coma looks really bad in the lenstip samples. 

Astro landscape photography is actually very popular these days with landscape shooters. Non-landscape astro work is still a very small segment though. 

Most landscape astro shooters might not be very tempted to purchase a 20 f1.4 lens, when a 15-30 f2.8 zoom does a great job. The 20 f1.4 would have needed to be exceptional in coma and vignetting to get sales out of them. 

The f1.4 is deceiving as well. If vignetting correction is applied to this lens, it will be pushing the corners by 3 stops, which is really bad. A Tamron 15-30 or Nikon 14-24 have far better transmission in the corners and need much less correction. That f1.4 advantage is not so great when every portion of the frame is considered. 

If I was buying new astro landscape gear, I would use the Tamron 15-30 with an astro tracker if I wanted even more light gathering.


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## rfdesigner (Nov 7, 2015)

PhotographyFirst said:


> PVS said:
> 
> 
> > I'm aware of that it's just that no one seems to get it how hard it is to design lens like this anyway, not many 21mm lenses on the market and even less with aperture faster than f/2.8 and, frankly, among those 2.8 21mils there very few of the ones with acceptable performance wide open.
> ...



I'm yet to find any EF-fit lens wider than F2.7 in the corners, there might be one, but it will be F2.6 not F1.4

(i.e. F2.0 + 0.7 stops vignetting or F1.2 + 1.5 stops vignetting)

EDIT: in fact, the humble 28 f1.8 is the brightest wide angle EF-fit lens at F3.5 in a FF corner


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## 9VIII (Nov 7, 2015)

I'm re-considering whether I would rather have this or the 18-35f1.8.
Most f1.4 lenses do not score well in light transmission, where the 18-35 does, but maybe those light transmission scores have more to do with vignetting than center brightness?

On crop the 20mm Art has less distortion, less vignetting, and is maybe 2/3 of a stop faster than the 18-35. If you're looking for a good 35mm prime replacement for your crop body camera, the 20mm Art is probably a really good choice.

Sometimes it's nice to zoom a bit, occasionally I'll take the18-35 out to 35mm(56mm FF Equivalent) to get a perspective appropriate for portraits, and sometimes the zoom is nice for adjusting the image when you have a tree branch or something just inside the frame, but generally I keep it around 22mm.

The 18-35mmf1.8 and 20mmf1.4 Art lenses will both make fantastic crop body lenses, choosing between the two would be tough.


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## Djaaf (Nov 9, 2015)

PVS said:


> It's hard to believe people are actually complaining and being disappointed by this lens in this thread. If the real samples are anything up to LensTip results then we have a really unique UWA lens here. Disappointing - compared to what!? Seriously.



Well, compared to what it could have been of course !  
I don't really need wide apertures and wide angle for anything other than nightscapes, milky way and aurora shots (I don't do events or hand-holding architecture shot at the blue hour or something otherwise needing that wide an aperture with that wide an angle). 
At the moment, all these are all done with Samy 14 f/2.8. 
On a 6D, that gives you something like 20sec exposure at f/2.8. Quite a bit of light, but, let's be honest, there's never enough.  
So, a 20mm f/1.4 was quite attractive on paper... that meant something like 10 sec exposure at f/1.4, meaning a stop more of light. But with that coma... well... no milky way and no nightscapes... And i'm not ready to shell out 1000€ for a stop more light on the aurora. It's almost 2 trips to go see them. 

So yes, I'm disappointed and I probably won't buy that lens (except maybe used in a few years... ). 

I do agree that for some it's an unique lens even with that much coma, it's just not that good on the application I had in mind for it... 

Djaaf.


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## BeenThere (Nov 9, 2015)

If I owned this lens, I would still use it for astro set at f/2.8 where vignetting is better than 2.8 rivals and coma is acceptable. Not what we were hoping for, but usable for astro. Other low light use wide open at f/1.4, and really sharp landscapes at f/5.6 would be a bonus.

But I will not buy because I have most of these uses covered by other lenses.


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