# Sigma 50mm f1.4 EX DG HSM....are they any good?



## willrobb (Dec 1, 2011)

Has anyone used the Sigma 50mm f1.4 EX DG HSM? What do you think of it?

Reason I am asking is I am taking a friend 50mm lens shopping this weekend, he's tried my 50mm 1.2L and would get one but it's out of his budget. I'm trying to persuade him to get the canon 50mm 1.4 as I know it's a great lens, but he's got his eye on the Sigma 50mm 1.4 EX DG HSM. 

Rental isn't an option (Tokyo is great for buying, lousy for rental, most rentals are just very high end gear) and from what I can gather from reviews such as the one below, the IQ is pretty damn good with the Sigma but the autofocus really is lousy an results in a lot of missed chances. 

http://www.the-digital-picture.com/Reviews/Sigma-50mm-f-1.4-EX-DG-HSM-Lens-Review.aspx

My friend will just be using it for portraits and a walkabout lens as he's wandering Tokyo doing street shots. All just for fun.

Anyone got any anecdotes from their own experience? Most reviews I have seen are negative about this lens, but I'd prefer some real life opinions.

Thanks for your time.


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## willrobb (Dec 1, 2011)

Ooops, 

Sorry, should have mentioned he uses a 5DmkII perhaps.

Sorry.


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## Flake (Dec 1, 2011)

It's not the autofocus which is a problem with the Sigma, but the lens suffers a significant focus shift on stopping down. The autofocus makes a perfect selection, on say the eyes, the shutter release is pressed and the aperture closes to perhaps f/2 and focus moves by 6inches (guess for illustration), but now the focus is not where you put it and might render the shot useless. Other lenses also have this problem but with an f/1.4 aperture it's much more critical, buying the Sigma is like playing Russian roulette, you might get one which isn't quite so bad, or your photography might not be so DOF critical, but if so what's the point in buying it?


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## whatta (Dec 1, 2011)

Flake said:


> It's not the autofocus which is a problem with the Sigma, but the lens suffers a significant focus shift on stopping down.



can it be fixed with af microadjust?


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## neuroanatomist (Dec 1, 2011)

whatta said:


> Flake said:
> 
> 
> > It's not the autofocus which is a problem with the Sigma, but the lens suffers a significant focus shift on stopping down.
> ...



Unfortunately, no. AFMA is a constant adjustment, focus shift is a variable effect - not there wide open, changing in magnitude as you stop down, disappearing when the DoF gets deep enough to mask it. AFMA would work if you calibrated at a given aperture, e.g. f/2, then always shot at that same aperture. Not a very practical solution.


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## Flake (Dec 1, 2011)

whatta said:


> Flake said:
> 
> 
> > It's not the autofocus which is a problem with the Sigma, but the lens suffers a significant focus shift on stopping down.
> ...



It's way out, far too much to be fixed in microadjust. From Photozone:

_"The HSM ("Hyper-Sonic-Motor") AF is very fast and virtually silent. AF accuracy is a difficult topic for the Sigma. It seems to suffer from pronounced focus shifts when stopping down ("Residual spherical aberrations") which is probably the reason why many users report back- or front-focusing issues. "_

The only real work around is to use depth of field preview to focus which is not what I'd like to do. It also suffers from very poor border & corner resolution on FF, but then on a portrait lens that's not always undesireable.

http://www.photozone.de/canon-eos/522-sigma50f14eosff


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## whatta (Dec 1, 2011)

Flake said:


> The only real work around is to use depth of field preview to focus which is not what I'd like to do.



on the 400d it does not work, once you do DOF preview, you cannot take a picture.
---
btw AF again, what does the f2.8 AF point mean? does it meant that if I have a 1.4 lens it will not be able to use all the light from it? focus is always done when wide open..


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## aires (Dec 1, 2011)

i've had them both (on 40D and 5D classic), and kept the Canon.

The Siggy can make great pics, but the focus of mine wasn't reliable. Even after sending it back to Sigma. The problem wasn't the focus shift, it was just backfocussing most of the time on subjects at +/- 5 meters. But not all the time... Drove me nuts.


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## pwp (Dec 1, 2011)

I can report the identical problems as other posters. 
When it nails focus it's brilliant, but far too erratic to rely on. Pity.

Mine's off to eBay. 

Paul Wright


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## alipaulphotography (Dec 1, 2011)

I use it all the time. It is a great lens.

Both these sets were shot with it.

http://alipaul.com/travel/kos/

http://alipaul.com/travel/berlin-2/

So I have heard, it has better centre sharpness than the canon when wide open, which it what I primarily use this lens for.

I don't have these focus problems others have spoken about.


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## willrobb (Dec 1, 2011)

Thanks for the info everyone, the "Russian roulette" analogy convinced me I will wrestle my buddy to the ground and drag him away from the Sigma cabinet if I have to. 

Much appreciation.


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## neuroanatomist (Dec 1, 2011)

whatta said:


> Flake said:
> 
> 
> > The only real work around is to use depth of field preview to focus which is not what I'd like to do.
> ...



Flake means manual focus with DoF preview. 

The f/2.8 AF point means it requires _at least_ f/2.8; anything wider is fine.


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## kirillica (Dec 1, 2011)

I was very disappointed with this lens and said myself: no Sigmas in my pocket anymore 
've got the same issues described above + ugly CA


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## dtaylor (Dec 1, 2011)

willrobb said:


> Thanks for the info everyone, the "Russian roulette" analogy convinced me I will wrestle my buddy to the ground and drag him away from the Sigma cabinet if I have to.



You'll be doing your friend a disservice.

The Sigma is much sharper then the Canon 50 f/1.4 at wide apertures, has better bokeh, and has much better build quality. The bokeh is amazing and the lens is actually usable wide open. I personally think it's the f/1.2L's equal. Some have AF issues, but if your friend is shopping in person then he can cherry pick the lens he wants on the spot. FYI, the AF motor in the Canon version is famous for having accuracy problems or just breaking over time.

I'm quite frankly surprised at the number of complaints here. Usually when the Sigma 50 f/1.4 comes up in forums the majority of reports are good.

As to AF issues...no doubt some units ship out of alignment. But I can't help but think that many complaints trace back to people struggling to use fast primes, especially since I've heard the same types of complaints from people who went with the Canon f/1.8 or f/1.4, and even the f/1.2L.

* f/1.4 is difficult for the AF system. This is true of any lens. DoF is stupid shallow at f/1.4 even on crop. On FF? Try one eyelash in focus.

* *Any* forward/backward movement on your part at wide apertures will move the focus away from where you want it. By the same token you cannot focus/recompose at wide apertures.

* Focus point indicators in the VF are not perfect. Usually the AF sensor points are larger than indicated. If the point is over a target which is not flat, the AF system may focus correctly but still focus somewhere you don't want. (DoF is that shallow.) 3D target areas that work just fine at f/4 or even f/2.8 may not yield the desired result at f/1.4 or f/2.

On a tripod pointed at a flat target the Sigma is about as consistent and accurate as the Canon 85 f/1.8. Perfection cannot be expected with super fast primes however. If you defocus, AF, and shoot 10 frames in a row, at 100% it will be clear that some shots are better than others even in this simple test. (I didn't have access to a Canon 50 f/1.4 when I did this. The f/1.8 is much worse than either the Sigma or Canon 85.) This is with a 7D which has an even better AF system.

I love fast primes, but all of them require some care in AF. There's something to be said for split screen manual focusing when using fast primes, and I've considered a KatzEye for this reason.

With that out of the way...I've shot kids (always in motion) with the Sigma f/1.4 with good success rates. And when you nail it...well...30" portrait prints at f/2 and f/2.8 are no problem at all, tack sharp and gorgeous.


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## kirillica (Dec 1, 2011)

dtaylor said:


> The Sigma is much sharper then the Canon 50 f/1.4 at wide apertures


lol, if you don't miss the focus 



dtaylor said:


> has better bokeh


with ugly CA  btw Sigma's bokeh is nothing compare to Russian Helios M40-2 analogue. If you prefer excellent bokeh - buy Russian stuff. 



dtaylor said:


> and has much better build quality


and cost  but who cares? Sigma was trying to make smth better than Canon and aimed to shoot art photography, but the 've got lose-lose situation: it's more expensive and not so good in CA as Canon's 1.4 and bokeh is much weaker than M40-2. So it's not "the best from both worlds". Not even close 

Mine Canon's 1.4 works perfectly from AF perspective. No complains so far (I normally choose the point for AF manually)


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## alipaulphotography (Dec 1, 2011)

dtaylor said:


> willrobb said:
> 
> 
> > Thanks for the info everyone, the "Russian roulette" analogy convinced me I will wrestle my buddy to the ground and drag him away from the Sigma cabinet if I have to.
> ...



Very wise words. Couldn't agree more. I'd recommend a precision focusing screen for any fast primes. I use one and I am more than happy with my images. I was so pleased with my 50mm sigma i also bought the 85mm f/1.4 - also superb! It also comes with a lens hood which canon refuse to add in with every non L lens they sell. The sigma is a new lens and has new technologies inside. The canon 50mm is a very dated old design, by no means bad, but it does need updating.

I see very little to no chromatic aberration in my images yet I do often notice it on images from canons 50mm. So I'd like to see some evidence of this.

More than happy with my sigma 50mm.


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## 92101media (Dec 1, 2011)

No personal experience with either lens, but from what I hear the Canon 50mm f/1.4 suffers the highest return to manufacturer rate of any Canon lens, primarily due to the AF ceasing to work at all. 

On the other hand, the Canon 50mm f/1.4 has higher average rating on B&H (4.7/5, and of those many of the negative reviews are probably due to broken AF) than the Sigma (4.4/5).

Another plus point for the Canon is that it's currently on sale at B&H for $339 vs. $499 for the Sigma. 

I wish Canon would release a Mk II version of the Canon 50mm f/1.4 that fixes the AF reliability issues.


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## neuroanatomist (Dec 1, 2011)

dtaylor said:


> But I can't help but think that many complaints trace back to people struggling to use fast primes, especially since I've heard the same types of complaints from people who went with the Canon f/1.8 or f/1.4, and even the f/1.2L.



I'd be inclined to agree, as the Internet is far from the fountain of Truth. 

But Bryan at TDP certainly knows his way around a fast prime, and he states, "...the Sigma 50mm f/1.4 EX DG HSM Lens has proven *very inconsistent* for me in the *focus accuracy* department. I have thrown out as many as 70% or more images from a single shoot of over 100 non-action, wide aperture shots because they were very OOF (Out of Focus)."

Likewise, Roger at LensRentals.com has probably used and tested more camera lenses than most people will ever even _see_ in their lives, and he states, "...the lens exhibits what I will term â€œschizophrenic autofocusâ€, i.e. when closer than 5 feet, it will front focus, further than 20 feet it will backfocus. This is not a calibration issue, itâ€™s just how it is."


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## willrobb (Dec 1, 2011)

dtaylor said:


> willrobb said:
> 
> 
> > Thanks for the info everyone, the "Russian roulette" analogy convinced me I will wrestle my buddy to the ground and drag him away from the Sigma cabinet if I have to.
> ...



I should have said I will "attempt" to wrestle him away, chances are he'd slip away and do his thing.

To be honest, I'm really keen to find out how the Sigma performs now, I get the feeling a good one may be pretty amazing, but a "dud" (which seems to be the majority unfortunately) are frustratingly bad.

Fast primes never really have perfect autofocus, to get the best out of them it's important to focus manually (as I often do with my 1.2L) but it is nice when the autofocus is fairly reliable in the situations where manual focus isn't an option.


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## photogaz (Dec 1, 2011)

The Sigma 50mm is one of my favourite lenses. This is coming from somebody who owns a 135L and 70-200 Mark II.

I'd say it can mis focus sometimes on distance objects but overall its an amazing lens. Unless Canon comes up with a new version, I would recommend the Sigma any day.


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## niccyboy (Dec 1, 2011)

I've heard very good things about it. 

I think it sits between the canon 1.4 and the canon 1.2...

It's a big boy, couldnt believe the weight on it.

Everyone I know that has it swears by it.


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## alipaulphotography (Dec 1, 2011)

Probably a try before you buy situation. I got mine 2nd hand and must have got lucky as mine is a joy to use.


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## dtaylor (Dec 1, 2011)

kirillica said:


> dtaylor said:
> 
> 
> > has better bokeh
> ...



Sorry, I don't care for the bokeh of the M40-2. It's unique for sure, and I've seen it put to good use in some shots. But it's very distracting and 'nervous' for most shots. I much prefer the smooth, diffused backgrounds of the Sigma.

Needless to say the M40-2 is a specialty lens (manual focus / stopped down metering / adapter required). On top of that, it's the wrong focal length for this discussion, it's not nearly as sharp wide open, and it does not have nearly the contrast as any of the 50mm lenses being discussed. Again, it has a unique look and that can be put to good use at times, but it's not a substitute for the lenses being discussed.

As for CA: the Sigma is worse than the Canon f/1.4, but much better than the f/1.2L. At any rate CA is pretty much a non issue on digital where it's easily corrected. And with the typical subject matter for these lenses you often won't even need correction. In fact, now that I think about it, I don't think I've used CA correction on more than 1 or 2 shots from my Sigma.


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## dtaylor (Dec 1, 2011)

neuroanatomist said:


> But Bryan at TDP certainly knows his way around a fast prime, and he states, "...the Sigma 50mm f/1.4 EX DG HSM Lens has proven *very inconsistent* for me in the *focus accuracy* department. I have thrown out as many as 70% or more images from a single shoot of over 100 non-action, wide aperture shots because they were very OOF (Out of Focus)."



He also only tested one copy  I should note that I don't see any where near a 70% throw away rate. Some shots will get tossed, but no more than with my 85 f/1.8.



> Likewise, Roger at LensRentals.com has probably used and tested more camera lenses than most people will ever even _see_ in their lives, and he states, "...the lens exhibits what I will term â€œschizophrenic autofocusâ€, i.e. when closer than 5 feet, it will front focus, further than 20 feet it will backfocus. This is not a calibration issue, itâ€™s just how it is."



This one interests me more because I imagine he has seen/tested more than one copy.

But again, this guy is going shopping, not ordering online. He can cherry pick to get one with decent AF characteristics.


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## neuroanatomist (Dec 1, 2011)

dtaylor said:


> As for CA: the Sigma is worse than the Canon f/1.4, but much better than the f/1.2L. At any rate CA is pretty much a non issue on digital where it's easily corrected.



Lateral CA - the red-blue tangential fringing away from the center of the frame - is easily corrected, automatically by most RAW converters including DPP. Longitudinal CA - the purple-green fringing throughout the frame - which is the bane of wide aperture primes, is not easily corrected, and in many cases, impossible to correct satisfactorily. At high-contrast transitions, the Sigma 50/1.4 suffers from some, but not much. The 50/1.2L is a lot worse - see the example in the PZ review of the 50/1.2L on APS-C. 



dtaylor said:


> But again, this guy is going shopping, not ordering online. He can cherry pick to get one with decent AF characteristics.



For himself, sure. But he also has to deal with the bitching of people who are unhappy with the rental, which is why he warns potential renters up front.


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## dtaylor (Dec 2, 2011)

neuroanatomist said:


> dtaylor said:
> 
> 
> > But again, this guy is going shopping, not ordering online. He can cherry pick to get one with decent AF characteristics.
> ...



Sorry...I ment OP's friend


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## neuroanatomist (Dec 2, 2011)

Oops...sorry, that should have been obvious. :-[


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## bchernicoff (Dec 2, 2011)

My trick with this lens is to half-press the shutter until it achieves focus lock and then release and repeat a couple of times until the lens doesn't refocus each time to achieve focus lock. Obviously, this doesn't work with any moving subject or when you only have a second to get a shot off.

From a image quality perspective, I love mine.


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## willrobb (Dec 3, 2011)

So we went out and played with 50mm lenses today:

canon 50mm f1.4
Sigma 50mm f1.4
Zeiss 50mm 
(canon 50mm 1.8 was dismissed on build and canon 50mm 1.2L were dismissed on poor build quality/cost.)

The Zeiss was dismissed on non AF grounds, even though IQ looked very good. I have to say the AF of the Sigma we tried was possibly the worst I have ever tried. It was a display copy, I realise it's probably had a lot of use and isn't as good as a lot of people have, but it really was all over the place and as a result the Sigma was passed over.

The canon f1.4 really suited my friend, the AF was great, the image quality awesome,he picked up an immaculate 2nd hand copy for a great price, we went out and tested it more and he was over the moon.

Thanks for the input everyone, I really appreciated it. We tested out as much as possible based on what I heard and my friend based his decision on what we tried. Had it been a better Sigma or a not so good canon it could have been a very different result, but with what we tried it was was it was.


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## niccyboy (Dec 4, 2011)

willrobb said:


> canon 50mm 1.2L were dismissed on poor build quality/cost.)



Poor build quality?


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## brandsteve (Dec 4, 2011)

The canon 1.2 was too much for our budget. We tried out the Canon 1.4 and with the 7D found the autofocus to be rather slow. It was a frustrating lens to use. We then tried the Sigma 1.4 and wow what a lens. 

I've heard the stop down issues with the Sigma 1.4 are mostly an issue on full frame cameras. We've had great results with ours. My wife has put her L zooms in the drawer and rarely takes them out now.


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## drmikeinpdx (Dec 4, 2011)

While I am certain that some lenses focus more reliably or faster than others, I feel that the whole DSLR autofocus system that is currently in use is loaded with potential problems and really needs to be replaced with something that will inherently compensate for the imperfect tolerances of both lenses and cameras.

My main camera is a 5D classic, which had a severe front focus problem when I bought it used. Canon fixed it for $200 and it worked fine with Canon lenses most of the time. After about a year, I upgraded from a Nifty Fifty to a Sigma 50mm 1.4 lens.

I found that the Sigma would front focus about 3-4 inches at full body portrait distance, but I liked the image quality enough that I learned to compensate by focusing on the model's ear instead of the eye. No micro-adjust on the 5D classic of course. The Sigma was my main lens for about a year.

Several months ago I bought a 7D and tried the Sigma on it, thinking that I would just dial in some micro-adjust. Doing some really precise testing, I did notice the focus shift with aperture changes, but it wasn't terrible. I decided to set the micro-adjust for the very slight back focus at f1.4 and ended up with only -1 compensation. Not bad, but obviously different than what I was used to with my 5D. 

I put the Sigma away around that time, because both the 5D and 7D were now sporting zoom lenses. (Crazy focus stories on those lenses as well.)

Last week, while at a group glamour photoshoot, we were going to shoot with available light and I thought f1.4 would be perfect. I got out my Sigma and did some test shots with the 5D to see where it was focusing so that I could compensate. 

I used a chess set in a "sun room" with large windows as my target and focused on the top of the white King. Magnifying the image on the LCD screen as much as possible, I was surprised to see that the Sigma was now focusing perfectly at f1.4. I shot two more times to verify and got the same results. I'll post one of these shots with a crop of the chess set. These are almost direct from RAW and my software applies minimal sharpening. Normally you would add a lot more.

If I had it to do over again, I'd probably buy the Canon 1.4 which at the time was $150 less, but I have enjoyed the looks I get from other photographers when they see that huge Sigma! 

But my real point here is that focus performance is almost completely unpredictable due to the trouble prone system currently in use. It makes perfect sense to me that people on forums like this disagree vehemently about how well a particular lens or camera focuses. I think the system must have been designed in an era when it seemed that small aperture zooms would completely take over the SLR world. Those of us who choose large aperture primes are stuck with a lot of frustration.

Mike in Portland, OR


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## willrobb (Dec 4, 2011)

niccyboy said:


> willrobb said:
> 
> 
> > canon 50mm 1.2L were dismissed on poor build quality/cost.)
> ...



Typo error on my part, poor build quality for the 1.8, the build quality of the 1.2L is awesome.


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## niccyboy (Dec 4, 2011)

Ahhh i see...

good luck with the canon 1.4!


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## Craig Richardson (Dec 5, 2011)

Might be a bit late to join the party here, but my brand new Sigma 50mm 1.4 is currently "in the shop". I had to take it over to Gentec International for calibration. Turns out they are located in Markham, Ontario about 10 mins away from my house, I don't think they get very many drop-ins but were very nice and immediately confirmed my front focusing issue on their own rebel body. I hope to get it back by the end of the week.


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## Mt Spokane Photography (Dec 6, 2011)

Since you mentioned that he has a 5D MK II, I'd say go Canon. The Sigma is a tad sharper on a crop, but the Canon is better on Full frame. 

A lot of responders have crop cameras, and will like it better.


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## skitron (Dec 6, 2011)

I've had two of the Sigma 50 1.4 and almost sent the second back as well. But then I tried shooting it without the B+H MRC UV and it focused just fine. So been using it ever since with no filter. The hit rate is not as good as my 100 L, but it hits in the low 90%s for me. Getting some very nice shots with it and glad I kept the second one. Very little focus shift on mine and that was the first thing I checked since it's all you see on the net about this lens.


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## carlc (Dec 6, 2011)

I have the Sigma 50mm f1.4 EX DG HSM on a Canon 7D and love it. A little more expensive than the Canon f1.4 but it is built like a tank. Great balance on a 7D, fast and accurate focus for me. I would buy another one if anything happens to this one. I am still learning some of the vast capabilities of this lens but it just kills low light challenges. Also own a Canon 24-105 and 10-22. Just waiting for the new 24-70 (if it has IS I will purchase). Also rented the new (II) Canon 70-200 and it is on my wish list right behind the 24-70.

I should note that I never used the Canon f1.4, just went with the Sigma f1.4 based on reviews and I don't regret it for a second. It will be on my 7D throughout Christmas.


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## Craig Richardson (Dec 7, 2011)

Craig Richardson said:


> Might be a bit late to join the party here, but my brand new Sigma 50mm 1.4 is currently "in the shop". I had to take it over to Gentec International for calibration. Turns out they are located in Markham, Ontario about 10 mins away from my house, I don't think they get very many drop-ins but were very nice and immediately confirmed my front focusing issue on their own rebel body. I hope to get it back by the end of the week.



Just a quick update, my Sigma was reprogrammed by Gentec and it is nailing focus now from a few quick tests I have run at close range.

EDIT: I was still having unpredictable focus shift problems until I read Skitron's post and removed my B+H UV filter and now close focus is good again. I really hope the far focus is fixed too because it was back focusing today at a distance.

EDIT 2: Lens is completely unpredictable, would not recommend at this point.


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## skitron (Dec 8, 2011)

Craig Richardson said:


> EDIT 2: Lens is completely unpredictable, would not recommend at this point.



One thing I noticed about mine was if the camera is not steady (i.e. good handhold technique) I will often get both motion blur and OOF. It's as if the AF can't deal with much camera motion and still do its job. Only an issue at low aperture values.

Another thing I'm going to try even though I'm having good luck with this lens is shooting in AI servo mode when at low aperture values due to the very thin DOF. Several folks are recommending this in the Canon vs Sigma 85mm thread and it makes alot of sense. May be worth a try for you.


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## Craig Richardson (Dec 8, 2011)

skitron said:


> Craig Richardson said:
> 
> 
> > EDIT 2: Lens is completely unpredictable, would not recommend at this point.
> ...



I can't get my head around how a lens can be so out of focus (like -11 needed to take a picture of the CN Tower because of back focus) but the phase detection can declare it in focus. What exactly did Sigma have to do to reverse engineer this focusing system? I also don't understand how this switches to front focus under 10 feet... or why when I use high quality B+H UV, CPOL, or ND filters the focus problems sometimes reverse themselves. Gentec has alot of work cut out for them when I bring this thing back again to them.

EDIT: I have done some light reading and came up with this gem:



> When you half-press the shutter release (or the * button, if you've used the custom function to move focusing control there), the activated AF sensor "looks" at the image projected by the lens from two different directions (each line of pixels in the array looks from the opposite direction of the other) and identifies the phase difference of the light from each direction. In one "look," it calculates the distance and direction the lens must be moved to cancel the phase differences. It then commands the lens to move the appropriate distance and direction and stops. It does not "hunt" for a best focus, nor does it take a second look after the lens has moved (it is an "open loop" system).
> 
> If the starting point is so far out of focus that the sensor can't identify a phase difference, the camera racks the lens once forward and once backward to find a detectable difference. If it can't find a detectable difference during that motion, it stops.


Source: http://www.zen20934.zen.co.uk/photography/Canon%20AF%20System.htm

So what basically happens is that when the camera gives the instruction to the lens to move, the Sigma lens understands that it is a move order but does not move precisely enough. Because there is no second check on focus, errors are left uncorrected. This is why AI-SERVO seems to work better because the camera is constantly looking at the focus and making corrections, it creates a closed loop and errors eventually reach zero, or so you would think! 

This also explains the strange pulsing behavior of this lens in servo mode because the camera is expecting the lens to nail focus after the first move order, but it doesn't so therefore the camera thinks the subject must have moved so it calculates a delta for subject shift and comes up with a move solution and tells the lens to execute, which it does but the lens screws up again, and so on and so on.

Another update: AI Servo works really well.


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## skitron (Dec 9, 2011)

Craig Richardson said:


> Another update: AI Servo works really well.



That's good to see. I'm having pretty good luck out of mine but this looks like it should make the percentages even better, plus maybe it works using a filter.

BTW, I get the same "pulsing" sensation with my 100 L when in servo, so it's not a Sigma specific thing. It's a bit smoother but definitely there.


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## smirkypants (Dec 22, 2011)

I have the lens and I like it. Don't love to bits, but like. But this post isn't about that.

Here's something to consider. I do almost exclusively outdoor shooting and have several expensive ND filters to be able to hit the max 250 flash shutter sync speed wide open (yes, I know, I should have bought a variable to begin with, but didn't), plus a graduated ND and a polarizer. These were all 77mm because I own a 70-200/2.8, a 17-55/2.8 and a 100-400. I have other sized filters, but my big money is in the 77s.

So I was going back and forth on the Canon 1.4 vs. Canon 1.2 vs Sigma 1.4 when it occurred to me that the Canons use 58mm and 72mm, respectively and the Sigma 77mm. To be honest with you, this made it an easy decision for me. First, I didn't have to buy a bunch of new filters that may have doubled the cost of the lens, and second I didn't need to add weight to my camera bag.

It's something to consider.


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## whatta (Dec 22, 2011)

smirkypants said:


> Here's something to consider. I do almost exclusively outdoor shooting and have several expensive ND filters to be able to hit the max 250 flash shutter sync speed wide open


could you show me few examples (pictures) of this technique? I wonder what is it for. : Thanks a lot.


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## catz (Dec 22, 2011)

I have Sigma 50 mm 1.4 EX DG with 5D mark II.

- It is a good lens (I am going to keep it)
- However, it is not perfect:
- All Sigmas have a bit less neutral color balance compared to Canon L. The 50 mm Sigma is no exception. It must be lens coating or something, but similarly than 12-24 EX DG, this 50 mm has a slight tint into yellowish.
- There is some chromatic aberration on out of focus areas, more than for example in Canon 70-200 2.8 L IS USM.

I have sort of stated to love the neutral (non-tinted) look of Canon L, and I think the only lens I would possibly trade this Sigma would be Canon 50 mm 1.2L. It is very expensive so not going to happen anytime soon. 

I love the 50 mm on full frame since it is useful as general purpose lens. On crop sensor I could find hardly use for the lens except for maybe portraits. I can do even landscapes with this on full frame. 

I have tried the lens on 60D but I was dissatisfied with the field of view.

For crop sensor a good alternative lens for giving 50 mm field of view is Samyang 35 mm F1.4. It has similar performance than the Sigma and has the best manual focus ring of the lenses I have used. It has also build quality and robustness comparable to a big Canon L. I don't think the 50 mm Sigma is a good choice for crop sensor unless you are looking 75 mm field of view (which incidentally I get out of my 70-200 on full frame which has more neutral color balance IMHO).


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## JR (Dec 22, 2011)

catz said:


> "" I think the only lens I would possibly trade this Sigma would be Canon 50 mm 1.2L""



I had the Sigma 50 1.4 before buying the Canon 50 1.2L a little over a year ago. Overall I found color rendition to be better with the L lens then with the Sigma one...Now because it is much heavier then the Canon 50 1.4, not sure I would get the Sigma over the Canon 1.4 if I did not have the 1.2 already.


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## smirkypants (Dec 22, 2011)

whatta said:


> smirkypants said:
> 
> 
> > Here's something to consider. I do almost exclusively outdoor shooting and have several expensive ND filters to be able to hit the max 250 flash shutter sync speed wide open
> ...


I think that's probably way beyond the scope of this thread, but here's a link to the strobist web site that explains how the process is done: http://strobist.blogspot.com/2010/06/using-nd-filters-to-kill-depth-of-field.html


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## skitron (Jan 10, 2012)

catz said:


> For crop sensor a good alternative lens for giving 50 mm field of view is Samyang 35 mm F1.4. It has similar performance than the Sigma and has the best manual focus ring of the lenses I have used. It has also build quality and robustness comparable to a big Canon L.



Just received a Rokinon branded Samyang 35mm and very pleased with it. I did the Nikon mount and use a Nikon to EOS adapter with AF confirm chip. I got a great price on it and figured I'd rather do an adapter than get a Canon mount and try to afix an AF confirm chip to it. I've only shot a few shots so far and I'm impressed with sharpness at f/1.4...better than my Sigma 50 at f/1.4. The lens has an excellent build quality, reminds me of the 100L.

Note about manual focus: With a AF confirm chip you can shoot in aperture priority (which I almost always do anyway) or manual with floating ISO. Plus if you run Magic Lantern unified, you have the choice of focus peaking in live view (paints in focus areas) and also focus trapping in non-live view. 

With focus trapping you half-press the shutter button then twist the focus ring while keeping the selected AF points in viewfinder on the desired target. As soon as it is in focus, it takes the shot. Very fast and effective when shooting in Av mode. Note it requires MFA to be set which of course is off by a mile due to thickness of the adapter. Hopefully the programable EXIF adapters have enough MFA programability to deal with it (which I would assume they do otherwise why put it on there?). I have a fixed EXIF adapter now but have a programmable version on the way and will post findings when it gets in...


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