Tuesday
Jun222010
The Complicated Relationship: The Sigma 50mm 1.4 reviewed
Tuesday, June 22, 2010 at 1:40PM 
[col-sect][column]I think it's fair to say that most of us try to "upgrade" when we move from one relationship to another. Usually, we compile a mental list of "never agains" as we are ejected from the previous situation: "Never again will I date a guy who is clinically depressed." "Never again will I marry a woman with an eating disorder." "Never again will I work for a Big Box Chain." Most of the time, this doesn't actually help us find healthy, fulfilling relationships the next time around; just unhealthy relationships without the particular idiosyncrasies we were most upset about as we left our last relationship. We humans have a way of focusing on the emendate problem to the detriment of understanding how and why we got in the situation in the first place.
I bought the Sigma EX 50mm f1.4 HSM after a having my heart broken by Canon's 50/1.4 USM one too many times. There are other articles that can get into it better than I'm willing to, but basically the elements on the Canon are too heavy for the light weigh clutch on the USM auto focus motor and so, eventually, it fails. The first time it failed, I had it rebuilt by Canon, then 18 months later it died again and I gave up. So as I was trying to recover from my frustration, my "Never Again" list for a 50mm lens looked like this:
- 1–Never again will I buy a lens with an auto focus system that can't deal with heavy use.
- 2–Never again will I buy a lens with heavy flair when it's wide open.
- 3–Never again will I buy a lens that can't seem to render detail wide open.
- 4–Never again will I buy a lens who's max performance doesn't show up tell f8 but goes away by f16 (I never seem to be at f8.)
- 5–Never again will I buy a lens with a composite barrel.
So that basically left me with the Canon 50/1.2 or the Sigma (I shoot journalism for a living so I didn't see the Zeiss as on option.) I went with the Sigma because I could almost buy three 50/1.2s for the price of the Simga and because I've LOVED my Sigma 24/1.8.
How is it? It's complicated. It's probably the best SLR 50/1.4 I've ever shot with one Giant Caveat: There are serious sharpness issues wide open at close distances. It's not a simple lens.
On one hand:
1–It's HUGE: 77mm front filter.
2–It's heavy: with a 2.7" barrel filled with glass, it comes in just over a pound!
3–The AF isn't quite as snappy as the Canon 50/1.4 (but what is?)
On the other hand:
1–It has great contrast all the way through the aperture range.
2–It has wonderful color.
3–It's well built.
4–By f2 it's is sharp at any distance.
5–The AF is accurate and built on a more robust technology than Canon's consumer USM.
6–It's really sharp at f1.4 at most middle distances.
7–The Boken is really smooth and pretty.
The Possible Deal Breaker
The close focus thing is a huge disappointment to be sure. Basically it means that if you are shooting a vertical head shot, you are going to have to be at f/2 unless you like wedding photography from the 1970s... which I don't. It's not that it's hazy, just that there is no micro detail. It's like a painting. Once you stop down to f/2 the problem is gone, along with most of the vignetting.
(Canon 5D Mark ii 50mm ISO-100, 1/80, f/1.4) click for full res
(Canon 5D Mark ii 50mm ISO-400, 1/80, f/2.8) click for full res
What's fascinating is if you take just a few steps back (two or three feet) the whole problem goes away and it's really sharp at 1.4 again! I have zero idea as to what is happening or why, but there it is. The one flaw in this lens. For about $500, you aren't going to get goddess, but you are going to get something you can live with for the rest of your life.
(Canon 5D Mark ii 50mm ISO-100, 1/80, f/1.4) click for full res[/column]
[column]If you've shot with something like the Canon 50/1.2 L or the Leica f/1.0 Noctilux then you know that most high performing lenses have these really strong weak spots simply because you can't get a lens to do everything all the time with out it costing as much as a new car. The f/1.0 Noctilux has sharpness issues at certain distances–and horrible vignetting as well–while the Canon 50L can't hold onto detail at f/16 for some reason.
Now that we've gotten the deal breaker out of the way, let's go over the rest of the lenses performance.
Like a lot of fast lenses, it's widest aperture doesn't really let it as much light as you might expect wide open because the vignetting is so pronounced that it effects most of the image. I found that for the Sigma, stoping down to just f/1.6 and pulling back my shutter by 1/3rd gave me back most of my exposure. By f/2 it's mostly gone and at f2.8 it's gone from a practical stand point. It's sharp enough in the corners by f/2 and technically sharp in the corners two stops later. All this puts in just about on par with the Canon 50 L for about 1/3rd of the cost.
(f/1.4)
(f/2)
(f/2.8)
Flaire
With it's enormous front element, I expected the Sigma to be really vulnerable to flare, but what I found was that it holds it's own as well as anything else in it's class. It has a nice shape to flare at f/16 and at it's not out of control wide open.
(F/16)
(F/1.4)
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Reader Comments (8)
Don't you know portraits are supposed to be done with an 85mm f/1.4 or f/1.2? That's the rule Shuler! Jeez! You *would* be doing headshots with a 50mm - what are you trying to do to the rest of us, eh? I'm suprised you haven't switch to a 35mm f/1.4 yet for portraits...rebel, you make me sick.
Really though that close focus shot is remarkably different from the shots at medium distances - on one hand, at that distance you're working with an ultra-ultra shallow DOF - you've probably got what 1/2 - 1" of DOF to work with at that distance and aperture? Not much is going to be in focus for sure but as you pointed out, even the parts of that shot that are in focus are lacking in sharpness in detail. The thing I must ask, however, is if you are *really* sure that a Zeiss 50mm f/1.4 ZE is totally off the table - if this is the kind of photograph you like to take (and this seems like a very Jon Shuler kinda-photo) there's no way you're using AF on this or need to - not that you *can't* use AF - but on this kind of shot you have time to compose and focus and you've got a pretty still subject - plus AF confirmation on the ZE...so...I don't know man, seems like for what you use and want your 50mm to be you might be able to get by with a ZE - the ZE is a sweet lens, spent some time with one when I was home for the Holidays...the macro 50 f/2 is sharper but totally impractical for what you're doing - sorry, I ramble.
It's a shame that Canon doesn't offer a more robust 50mm f/1.4 - I don't feel like a pro-grade 50mm f/1.4 would really compete with the f/1.2 L - if you need that extra half stop, you need that extra half stop - but not everyone does...or DO they - but you know me, give me fast or give me fast or give me death.
You could always get a Sony Alpha + Zeiss 50mm f/1.4 with AF...but you'd have to use an Alpha.
I have been using the Sigma 50mm f/1.4 for a couple of weeks now on a simple Canon Rebel T2i.
At f 1.4 I get pictures similarly soft to what you show. What I discovered is that the lens front focuses a lot.
I used a few test charts and a tripod and was able to demonstrate/repeat the front focus issue. This issue was very pronounced at a distance of 48" from the target (using a single/center AF point).
I tired another 50mm in at the store where I bought it with the same issue. i also tied my lens on another Canon T2i.
Hence the loss of sharpness is possibly more an issue of not properly focusing.
I hope sending the lens and camera to Sigma for calibration may fix this issue and yields sharp/clear images at f 1.4.
Thanks for the info man. Please keep us in the loop ad you figure things out. :)
I just received the Sigma 50mm f/1.4 back from calibration and it works quite well with my camera now. On August 13th I send the lens including my Canon T2i to Sigma and a fairly short 10 days later got everything back. The service people at Sigma uploaded a new firmware to the lens and tested the camera/lens system and it works very well now. Front focusing issues are mostly gone. The lens is fairly sharp at even f/1.4 setting now.
I noticed the same haze problem with the sigma at close distances. This seems to be mostly caused by focus shift. If you take a shot at f/1.4 and another at f/2.8 of the same scene at close distance without refocusing, then you will see the f/1.4 shot focussed slightly in front of the f/2.8 shot. The f/1.4 shot is really a composite of the out of focus f/2.8 light, the somewhat in focus f/(2.0-2.8) light, and the in focus f/(1.4-2.0) light. As the distance increases, the depth of field of all apertures increases and eventually overtakes these focus differences. The lens might also be better corrected for this at greater distances. It would not surprise me if the focus shift did really weird things to the autofocus accuracy.
It is a real shame that the lens does not clear up until a few feet beyond where I often like to use it.
I can see in your example shot that there is a spot in sharp focus. Now maybe that wasn't your autofocus point, but the lens is not "soft." It has an extremely shallow depth of field at close range and f/1.4, so there will be lots of the picture that is blurred. I suspect the issue is incorrect autofocusing, not a "soft" i.e. aberrated, lens.
I would say AF accuracy is, in fact, the issue the more I use the lens. It's confusing at first because the bokeh at 1.4 is very dreamy, almost hilated in a way so it looks like aberration when it misses and nothing appears to be sharp. That's still a pretty big issue though.
I agree, I've been researching these lenses because I am thinking about buying one. Apparently, from other forums, Sigma will calibrate the auto-focus for you, but you have to send your body in with the lens. People have said that once it comes back the autofocus is nearly perfect.
Hopefully I won't have this issue if I get one!