# Sigma 24mm f/1.4 Art first resolution testing posted - LensTip



## ahsanford (Mar 9, 2015)

Imperial Captain: "Our first catch of the day."

From Lenstip:
http://www.lenstip.com/index.php?test=obiektywu&test_ob=430

_"It is obvious at once that the 1.4/24 model is far more difficult to produce than the 1.4/35. In a range from f/5.6 to f/16 both lenses are practically indistinguishable but in the f/1.4-4.0 range the lens with a longer focal length prevails decisively."_

I know resolution isn't everything, but clearly Sigma had a harder job at 24 than they did at 35 or 50.

- A


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## raptor3x (Mar 9, 2015)

It appears it's just about as bad in the coma department as the Canon and Nikon versions. That's a bit disappointing .


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## candc (Mar 9, 2015)

it looks to be good but not as exceptional as some of the other sigma art lenses. there are some sample shots that look really bad. 

all and all pretty disappointing. the chart below is what they posted for the 18-35, according to them it has more resolution? i don't know that much about lens design but if you can make a 18-35 f/1.8 zoom that works on ff @ 28mm then this lens shouldn't be that difficult to produce.


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## TommyLee (Mar 9, 2015)

I like the way lenstip reviews

I had the canon 24 1.4 mark I ....just gave to brother for his 50D...
....it was worth about $900 used..... not so much NOW....with the sigma
I had rented the 24L mk II a few times..... less chromatics, really big vignetting....decided not to buy

this sigma is a little betterwith coma than the canon 24L mk II....(first 2 lenstip shots compared)

astig : canon = 6%, sigma = 7%
[ lenstip reviewer got confused on sig 24 note.. and said earlier 24L was 2% - that was their crop camera number ]
the coma on sigma is a little nicer behavior... but not anyway near as nice as sig35 1.4.

this is why - IMO - sig35 looks so good, has such clarity over my 35L (last 2 lenstip shots compared)
....and the 35L was a nice lens ...I liked it...without seeing its coma....ha...
just sigma got it better..

so I MAY consider the sigma 24 for shooting in a dark club, where only the sigma35... and 85L was suitable for me (dont ask about THAT coma..yikes)
I knew the canon 24 II had to get beaten...but not sure this as exciting as I had hoped.
the exciting thing is a little better at 1/2 the price...
If I am gonna shoot in the darkness of a club, I want a little wider for composition of a few players etc..

I might add ....a fast 24 in the garden makes for nice flower compositions with blurred backgrounds...
would like to SEE bokeh..

goodnight prayers:
- I would so love a 135 stabilized lens @ f1.8/f2....please sigma ...or canon....do this
- I really want these same lenstip resolution and coma measurements etc
...on the tamron 15-30 and canon 11-24.....


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## ahsanford (Mar 9, 2015)

candc said:


> it looks to be good but not as exceptional as some of the other sigma art lenses. there are some sample shots that look really bad.
> 
> all and all pretty disappointing. the chart below is what they posted for the 18-35, according to them it has more resolution? i don't know that much about lens design but if you can make a 18-35 f/1.8 zoom that works on ff @ 28mm then this lens shouldn't be that difficult to produce.



I'm no lens design whiz but these reviews constantly show a rosier picture for APS-C as compared to FF, especially in the corners of an UWA large aperture lens. FF corners on wide focal lengths are where expectations go to be crushed. 

That said, this lens is no slouch. I imagine street and environmental portraiture folks would really smile at that wide open center performance. And this lens represents a clear value proposition to the nearly 2x priced 24 f/1.4L II. It's just doesn't have the face-meltingly strong performance of the 35 and 50. 

Sigma doesn't hit home runs every time at bat, but this is still a solid base hit.

- A


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## TommyLee (Mar 9, 2015)

ahsanford said:


> And this lens represents a clear value proposition to the nearly 2x priced 24 f/1.4L II. It's just doesn't have the face-meltingly strong performance of the 35 and 50.
> 
> Sigma doesn't hit home runs every time at bat, but this is still a solid base hit.
> 
> - A



+1 the way you put it....


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## Random Orbits (Mar 9, 2015)

_Still the speed of the mechanism is something you can complain about. Even in good lighting conditions running through the whole distance scale and setting the focus can take over one second. It also seems that running from the infinity to the minimum focusing distance takes a bit less than the other way round. Both the Canon and the Nikkor were almost two times faster and in the case of the Canon its ring turns through as much as 160 degrees, having definitely a bigger range than 90 degrees of the Sigma ring.

When it comes to the accuracy of the mechanism we don’t have any serious reservations. The average number of misses in studio conditions didn’t exceed 5%. During the outdoor photo session the Sigma coupled with the 5D MkIII missed more often so we decided to perform another test. We put the lens on a tripod in our studio, in front of our biggest resolution testing chart and took 50 photos by f/2.8 changing the focus each time. The highest vertical MTF50 value amounted to 2112 LWPH and the lowest was 1968 LWPH; the median amounted to 2048 LWPH. The worst result we got was just 7% or so worse than the best so you can assume the repeatability of the autofocus settings is very good._

The Sigma is much slower to AF than the Canon/Nikon, and its focus accuracy is worse. So, it has a slight edge wide open compared to the Canon in resolution, but Canon catches up at around f/2 and has a very slight advantage beyond that. But then this is for optimally focused images... in the real world, it's AF accuracy is worse, which weakens its resolution advantage at f/1.4 and could make it significantly worse at smaller apertures. Wish they had noted under which circumstances the AF tended to miss more. Also wish they had performed their studio test at f/1.4 instead of f/2.8 ...


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## mackguyver (Mar 9, 2015)

Random Orbits said:


> The Sigma is much slower to AF than the Canon/Nikon, and its focus accuracy is worse.


I noted that as well, and it seems to be the Achilles' heel for their Art lenses, at least from what some of the members here have reported. I have the 24L II and I'm not surprised to read the results. The vignetting seems to be the biggest improvement here, although that's not necessarily a big deal for most of the intended uses of this lens. I'm planning to sell my 24L II as I don't shoot events anymore and the 11-24 f/4 and 24-70 f/2.8 II have replaced it in my bag for landscapes.


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## lintoni (Mar 9, 2015)

The coma looks a bit disappointing... I was hoping that this would be a great lens for astro...


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## Random Orbits (Mar 9, 2015)

mackguyver said:


> Random Orbits said:
> 
> 
> > The Sigma is much slower to AF than the Canon/Nikon, and its focus accuracy is worse.
> ...



So are you going to keep the 16-35 f/4 IS?


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## mackguyver (Mar 9, 2015)

Random Orbits said:


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


The jury is still out on that decision... The 11-24 is as good or better (lower CA, vignetting & distortion) but about 10% as practical.


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## ahsanford (Mar 9, 2015)

mackguyver said:


> The jury is still out on that decision... The 11-24 is as good or better (lower CA, vignetting & distortion) but about 10% as practical.



For a person who waited as long for the 16-35 F/4L IS as you did, I'm shocked you'd even consider shelving it for the 11-24 F/4L.

Surely, handholdability + front filterability + IS would earn it a place in your bag. I could not imagine walking away from those three items just to chase the bendy from 11-15mm, but -- as I must remind myself -- _I am not you_. 

- A


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## NancyP (Mar 9, 2015)

Well, I don't need the Sigma 24 Art. The coma is a bummer. I was hoping for low coma for night photography purposes. I hate it when my stars have wings! My current lens at this approximate focal length, Zeiss 21 f/2.8, can't be significantly bettered other than with a faster aperture. (hush, you owners of 24 f/3.5 TS-Es, Zeiss 25 f/2, etc - I said "significantly" bettered). Most of my night shots are taken with Zeiss 21 @f/2.8.


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## mackguyver (Mar 9, 2015)

ahsanford said:


> mackguyver said:
> 
> 
> > The jury is still out on that decision... The 11-24 is as good or better (lower CA, vignetting & distortion) but about 10% as practical.
> ...


Exactly what I'm thinking. The 11-24 is pretty spectacular, but the 16-35 f/4 IS is just the same in it's own way, so I can't imagine selling it.


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## Zenergy (Mar 11, 2015)

lintoni said:


> The coma looks a bit disappointing... I was hoping that this would be a great lens for astro...




I second this thought. I was hoping the same. But it looks very disappointing indeed. 

Am I the only one that feels like this lens isn't sharp enough? I am comparing it with my 22mm f2 pancake.


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## Pixel (Mar 30, 2015)

Pretty disappointed with my Sigma 24 1.4 A. 
The problem I'm having with it is that yes it focuses tack sharp ONLY WHEN I use the center focus point on my 7D Mark II. When I move the focus point to the far left or right, the focus (in ONE SHOT mode) becomes very erratic, sometimes just bounces around all over the place and when it lands it's way out of focus. 
I cannot repeat this problem with my 11-24 f4 nor can I repeat this problem with my 24-70 f2.8 II. 
Not looking good for the Sigma that I had such high hopes for. 
Perhaps I just got a bad copy I don't know. I've always been a "Canon snob" in the past and just turned my nose up to off brand lenses for these types of reasons but based on the glowing reviews I've heard I thought maybe I'll rethink my snobbish attitude and try this new Sigma.
May have been right all along.


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## BeenThere (Mar 30, 2015)

Agree that coma at F1.4 and F 2 is disappointing. However, by F2.8' the coma is not so bad, sharpness has improved, and vignetting is only a half stop. It's kind of a shame to have to use this lens at F 2.8 for star shots but it's much better that a lot of native 2.8 lenses that are used for stars.


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## ahsanford (Mar 30, 2015)

Pixel said:


> Pretty disappointed with my Sigma 24 1.4 A.
> The problem I'm having with it is that yes it focuses tack sharp ONLY WHEN I use the center focus point on my 7D Mark II. When I move the focus point to the far left or right, the focus (in ONE SHOT mode) becomes very erratic, sometimes just bounces around all over the place and when it lands it's way out of focus.
> I cannot repeat this problem with my 11-24 f4 nor can I repeat this problem with my 24-70 f2.8 II.
> Not looking good for the Sigma that I had such high hopes for.
> ...



I can't speak to your snobbery D), but we can see if the AF has been problematic elsewhere.

LensTip tested focus _speed_ (decent, but not super quick) and focus _repeatability_ (good), but they did not specify if they tested off-center AF points. But they did list having occasional misses on a 5D3, which is somewhat odd. Typically, I thought those who complain about poor AF in third party lenses are doing so with older camera bodies.

- A


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## Pixel (Mar 30, 2015)

One more note on the Sigma off center AF problem, I went down to the camera store and tested a different 24 1.4A in addition to a 35 1.4A on a 7D2 off of their shelf (not mine) and noticed the exact same problem in those two lenses when shooting off center AF. There must be hardware or firmware problems in relation to the 7D2. That's my only conclusion. 
I'd love to hear other thoughts and test results.


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## ahsanford (Mar 30, 2015)

Pixel said:


> One more note on the Sigma off center AF problem, I went down to the camera store and tested a different 24 1.4A in addition to a 35 1.4A on a 7D2 off of their shelf (not mine) and noticed the exact same problem in those two lenses when shooting off center AF. There must be hardware or firmware problems in relation to the 7D2. That's my only conclusion.
> I'd love to hear other thoughts and test results.



I've shot the 35 Art and I constantly used off-center AF points. With _that_ lens, I shot off-center plus-shaped clusters (i.e. '+' pattern of 5 points) or often single AF points given that f/1.4 can be unforgiving to larger AF selection areas. 

But I'd give that AF a B. Consistency and speed were quite good but not world class. As an amateur, I had misses, but most of them were from misusing such a wide aperture on relatively close subjects and not due to the AF. 

But I can't speak for the 24 Art. I've never shot it.

- A


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