Sigma Launches 20mm f/1.4 DG HSM Art

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.)

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.

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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Berowne said:
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.)

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.

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?

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

notation_mtf_plus.gif
 
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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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Rudeofus said:
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.

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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Rudeofus said:
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.

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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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 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.

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


Djaaf.

+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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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.

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


Djaaf.

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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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

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

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


Djaaf.

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.

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. :P

- A
 
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ahsanford said:
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

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

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


Djaaf.

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.

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. :P

- A

LoL. Good point. :)
 
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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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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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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's talking monkey's nodding], on Flickr

Milky Way by OverdeaR [donkey's talking monkey's nodding], on Flickr

Milky Way Galaxy by OverdeaR [donkey's talking monkey'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's talking monkey's nodding], on Flickr


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

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.

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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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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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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