# Testing the Sigma 50mm Art lens in my style of photography



## drmikeinpdx (Oct 22, 2014)

I've been really curious about the Sigma 50mm F1.4 DG HSM, aka: the 50 Art lens. I've read a lot of reports about autofocus problems, but wanted to check it out for myself.

I rented a copy of the Sigma 50 Art from LensRentals.com. Before I ordered, I emailed their customer service to ask if they used the USB dock to do any kind of calibration with the lens. They replied that they take every 50 Art that comes back into the shop, put in on the USB dock and reset it to the default values. That sounded good to me, as I planned to use the microfocus adjust feature on my 5D3 to make any needed changes. I was planning to do an outdoor photoshoot where my models would always be roughly ten feet from the camera, so I did not feel like I'd need the USB dock to adjust the focus for different distances.

Upon receiving the lens, I did my usual autofocus calibration. This time only at ten feet. Using the center focus point, the Art lens was pretty consistent on my 5D3. I settled on +3 MFA value and was pretty pleased with the stable focus from shot to shot.

Then I tried using other focus points. I found that as you move away from the center point, the lens will front focus more and more. Using the outermost horizontal points, the front focus was about two feet or a 20% error. The next pair in toward the center front focused about one foot or 10%. Using the top and bottom points, the front focus error was about 1 foot or 10%.

When the lens was in focus, it was very sharp, so I went ahead and did the planned outdoor photoshoot. I used mostly the center point, but occasionally moved the focus two spots left or right. Used within this restriction, I was very happy with the sharpness, bokeh and autofocus accuracy.

I did a few shots with my old Sigma 50 Classic, which was autofocusing pretty well that day, since I fed it a shot of cheap gin before leaving the house and said some magic words over it. The Art lens was definitely sharper, but not stunningly better. They both created very nice bokeh of the distant trees when used wide open.

Here is a shot with the Art lens at F/2.0:







Here's a shot with the Sigma 50 Classic at F/1.4:






These are just fun shots to give you an idea of what kind of photoshoot I was doing, they don't really prove anything.

One thing I learned on this shoot was that the DOF at 1.4 is even more shallow than I thought. Shooting two models standing side by side you have to make sure they are both exactly the same distance from the camera. Unfortunately couples naturally want to move around. I had a lot of shots where one model was in perfect focus and the other was slightly out of focus. I was kind of expecting that and shifted focus back and forth between the two models, so I got plenty of usable photos.

In the future, if I'm not going for the absolute maximum bokeh, I plan to use my Sigma 50 Classic primarily at F/2 on these kinds of photoshoots.

One more item... Before sending back the Art lens, I attached it to my old 7D backup body and ran it through my usual autofocus test. It was difficult to come up with a precise AFMA number because the focus was not very consistent. I settled on +12. I tried the outer focus points to see if the 7D showed the same error pattern as the 5D3. It did not, but the general accuracy and repeatability was poor enough that I would not venture a guess as to what the real pattern is. Basically, I would not want to use the Art lens on my 7D unless I stopped it down to about F/4 or so. As a control, I put my 40 pancake lens on the 7D. It focused better than the Art lens, but still not as well as I wished. I don't know about your 7D, but mine has never had a very accurate AF system, which is one reason I rarely use it now that I have a 5D3.

As a result of my experience, I have decided not to buy a new 50mm lens. I will keep using my Sigma 50 Classic and wait and see if Canon comes out with a new 50mm lens in the 1.8 to 2.0 range. If it is sharp wide open, it would be the perfect lens for me.

Update: I turned this photoshoot into a blog post that includes some additional photos taken with the 50 Art lens. Some are mildly naughty, so consider yourself warned. 

Check it out here: 

http://www.beyondboudoirphoto.com/blog/2014/10/outdoor-photoshoot-for-a-portland-couple


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## NancyP (Oct 23, 2014)

The reason to buy an f/1.4 lens is to shoot at f/1.4. If f/2 is better for your work, then a nice small image-stabilized 50 from Canon, should they ever get off their duff and produce one, would be The Ticket.


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## Quasimodo (Oct 23, 2014)

I bought mine on Monday this week. I have not had time to run it through Reikan yet. But from what I have seen so far it seems very sharp indeed. AF consistency I have not had a chance to discover as of now.


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## drmikeinpdx (Oct 23, 2014)

NancyP, I really liked Canon's 35mm stabilized lens when I rented one, but I need it in a 50.

Since there is no sign of one on the horizon, I may start researching the 50L lens.


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## Ripley (Oct 24, 2014)

drmikeinpdx, I rented the 50A from LensRentals earlier this week and my experience with it was identical to yours. 

Out in the field I was a little disappointed by the autofocus accuracy, but not surprised. I did several studio shoots using live view zoomed focus and the results were great. 

I'd say the 50A's sharpness was equivilant to my 24-70ii, 1-2 stops sooner. I wasn't exactly impressed with the 50A at 1.4 but it certainly beats the Canon 1.4 wide open all day long. IMO, the 50A really comes into its own at f2. I did most of my shooting there and love the results.

I would love to go all in on Sigma's Art line but I'm not sure if I can get there right now. I'm thinking about trying out the 50L and 85L next. I'm glad I got LensRentals HD...


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## zlatko (Oct 24, 2014)

drmikeinpdx said:


> NancyP, I really liked Canon's 35mm stabilized lens when I rented one, but I need it in a 50.
> 
> Since there is no sign of one on the horizon, I may start researching the 50L lens.



Thanks for your useful post. I too would like a nice compact Canon 50mm to match Canon's 35/2 IS. In the meantime, the 50L does the trick for me. It is not the perfect lens, but it delivers some wonderful images — it is easily one of my favorite lenses. 

I haven't tried the 50A, but those problems with the 50A would turn me away from it too. Sharpness is nice, but the entire lens is important. Being 20% or 2-feet off on the outer AF points is pretty bad. 

By the way, the 50L doesn't seem to AF very accurately on APS-C cameras either, at least the ones I've tried it with.


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## Ripley (Oct 24, 2014)

NancyP said:


> The reason to buy an f/1.4 lens is to shoot at f/1.4.



This is not entirely true. Maximum aperture is an option, not a mandate.


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## ajfotofilmagem (Oct 24, 2014)

A month ago, I have both 50mm F1.4, Canon and Sigma Art. Indeed, using focus points outside the center there is a discrepancy. I marvel at the sharpness of the Sigma Art wide open, while the Canon needs to be stopped down to F2.8 to achieve sharpness and contrast similar to Sigma. 

In fact, it is not very reliable for tracking moving objects. But it works wonderfully in live view, and I look forward to use in a body with Dual Pixel AF. 8) 

Whereas if you use the center focus point or live view, Sigma Art puts Canon 50L with shame in the aspect of sharpness wide open. Excuse me for heresy, but I have to say I prefer the bokeh of the Sigma too. :-X ??? :


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## Maiaibing (Oct 24, 2014)

Ripley said:


> NancyP said:
> 
> 
> > The reason to buy an f/1.4 lens is to shoot at f/1.4.
> ...



But it makes common sense. 

If you do not shot fast lenses wide open you are paying a lot for mostly no improved picture quality (with primes). Even with some zooms like the 70-200/f4 IS L and 70-200/f2.8 IS L there is no difference @f/4 (except the bokeh is actually better on the f/4-lens).

I need the fastest lenses I can get - but if I could get along with f/4.0 and f/5.6 my hobby would be a lot cheaper and my pictures just as good.


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## cayenne (Oct 24, 2014)

A few weeks back, I shot the 2nd annual New Orleans Bridal Crawl....it is for charity and involves a bar hop after the initial gathering. Its a fun party.<P>
I was shooting video on my 5D3 as I did last year. This year, I rented both the Sigma Art 50 1.4 and the Canon 50L 1.2.<P>
I shot stills with both...and what I gathered for my experience of the two...if I were buying ONLY for stills, I might lean towards the Sigma. Felt more solid and was sharp. 

However, from what I've read and saw in person, the extra special coatings on the Sigma, actually seem to make it a bit slower than 1.4. It almost seemed that it was about 3/4 of a full stop slower than the Canon.

I'm still wavering, but at this point, I'm leaning towards the 50L 1.2. I was able to shoot some MIGHTY dark bars with this and no additional lights with the 1.2 wide open.

So for when you need very low light...at this point, I'm leaning towards getting the canon 50L 1.2.

HTH,

cayenne


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## infared (Oct 24, 2014)

The lens is quirky ...but awesome!
I had to send my first lens back...but the second one seems to be very good.


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## dash2k8 (Oct 24, 2014)

Generally lens of the same focal length but bigger max aperture (50mm f/1.2 vs f/1.8) will be of better make and glass, thus producing superior image quality in contrast, sharpness, etc. No one would believe that a picture taken at f/2.0 with the 50mm f/1.2 would look the same as the f/1.8 lens. How many people actually shoot portraits at f/1.4? (I mean that as a serious question, not a rhetorical challenge.)

I think f/2.8 is the "magic number" in terms of what people will buy a lens to use at wide-open. Sports shooters need big aperture to keep up the shutter speed, while f/2.8 is a deep enough DOF to keep most of the athlete in focus. I don't think I've ever heard of a sports shooter buying the 135mm f/2 because he needs to shoot at f/2. The DOF would be too shallow and would make a lot of pictures useless.


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## Vern (Oct 24, 2014)

dash2k8 said:


> Generally lens of the same focal length but bigger max aperture (50mm f/1.2 vs f/1.8) will be of better make and glass, thus producing superior image quality in contrast, sharpness, etc. No one would believe that a picture taken at f/2.0 with the 50mm f/1.2 would look the same as the f/1.8 lens. How many people actually shoot portraits at f/1.4? (I mean that as a serious question, not a rhetorical challenge.)
> 
> I think f/2.8 is the "magic number" in terms of what people will buy a lens to use at wide-open. Sports shooters need big aperture to keep up the shutter speed, while f/2.8 is a deep enough DOF to keep most of the athlete in focus. I don't think I've ever heard of a sports shooter buying the 135mm f/2 because he needs to shoot at f/2. The DOF would be too shallow and would make a lot of pictures useless.



Well, if you shoot indoor sports, you definitely shoot wide open with the 135 and 200 f2 - all sports require many frame captures to get a few great shoots - and not just b/c the DOF is shallow. Also, take a look at the posts on the 200 f2 - beautiful portraits, wide open (IMO, to each his own).


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## VeloDramatic (Oct 24, 2014)

I own the 200 f2 and it's my go-to lens for sports, the core of my business and many other photographic assignments. I've not experienced any AF lens, owned or rented, that surpasses it. Having said that, I would only shoot at f 2.0 if I absolutely had to given just how shallow the DOF is. Stopped down to f3.5 is my sweet spot for my core sport cycling and backgrounds are still smooth as silk.

I just purchased the Sigma 50mm Art and without question it's a fantastic lens. It doesn't have the AF response of the 200 f2 but AF is great and the lens is exceptionally sharp. I'm just back from the Hebrides, and a landscape change of pace, where the Sigma 50 performed terrifically... including in portrait orientation with a RRS pano tripod setup for some really nice stitches.

For general photography on both FF and 1.3 crop (my bodies) the Sigma 50mm Art offers superb IQ and performance. I'll admit to having no interest in pixel peeping, the lens just works beautifully. Good purchase IMO.


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## drmikeinpdx (Oct 24, 2014)

Infrared and VeloDramatic... Glad you are having good luck with the 50 Art lens.

What body are you using your 50 Art on?

Do you use the outer focus points or mainly the center point?


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## Ripley (Oct 24, 2014)

Maiaibing said:


> Ripley said:
> 
> 
> > NancyP said:
> ...



There's a lot more to a lens than maximum aperture. Those other attributes can warrant using a lens without using it wide open.

For example, I rented the 50A and shot it most of the week at f2 because I wanted the increased sharpness, didn't need the extra stop of light, and didn't want the decreased depth of field.


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## zlatko (Oct 24, 2014)

VeloDramatic said:


> I just purchased the Sigma 50mm Art and without question it's a fantastic lens. It doesn't have the AF response of the 200 f2 but AF is great and the lens is exceptionally sharp. I'm just back from the Hebrides, and a landscape change of pace, where the Sigma 50 performed terrifically... including in portrait orientation with a RRS pano tripod setup for some really nice stitches.



It sounds like a great lens for landscape where you likely stopped down. But did you also try using it at or near its widest aperture? If so, was the autofocus good and accurate most of the time? I'm also curious which camera body you used with the 50 Art and whether the outer AF points performed OK. Thanks in advance.


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## infared (Oct 24, 2014)

drmikeinpdx said:


> Infrared and VeloDramatic... Glad you are having good luck with the 50 Art lens.
> 
> What body are you using your 50 Art on?
> 
> Do you use the outer focus points or mainly the center point?



5DIII single focus point...but move it around on the screen to where I want focus. It is a WOW lens...and I totally disagree with those that are saying I must use it at f/1.4... That is just foolish. I use it at varying f stops to get in focus what I want in focus in a particular image...could be f/1.4...or it could be f/3.5...whatever...and it is still sharper than all 3 of Canon's lens offerings as far as I am concerned.


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## ajfotofilmagem (Oct 24, 2014)

cayenne said:


> However, from what I've read and saw in person, the extra special coatings on the Sigma, actually seem to make it a bit slower than 1.4. It almost seemed that it was about 3/4 of a full stop slower than the Canon.
> I'm still wavering, but at this point, I'm leaning towards the 50L 1.2. I was able to shoot some MIGHTY dark bars with this and no additional lights with the 1.2 wide open.
> So for when you need very low light...at this point, I'm leaning towards getting the canon 50L 1.2.


There are some topics relating experiences with F1.4 lens in Canon digital cameras, I did not find now, but the conclusion is surprising: 

A member of CR did a test with an F1.4 lens (at F1.4) mounted on a Canon DSLR camera with all manual settings, and photographed a target with controlled lighting. Then he repeated the shot with everything the same, except that he put duct tape on the electrical contacts of the lens, so the camera could not identify which lens was being used.

He found that the picture looked darker when the camera could not identify which lens was being used. Neuro then gave a simple explanation and terrifying: 

Digital cameras (unlike film) do not capture well the light that hits the sensor at a very tilted angle. How F1.4 lenses (and more luminous) many light rays arrive at quite tilted sensor, and do not penetrate well into the photodiodes. To circumvent this problem, Canon pushes the ISO (in secret) to simulate the use of light rays that exists in the film. Ie. When you select ISO100, the camera secretly push the ISO up to 153 (for example) and compensates for the lower utilization of light rays.

If you select ISO 1600, the camera pushes secretly up to ISO 2129 (for example), and compensates for the lower utilization of light rays. In this case, the noise will be larger than an ISO 1600 "true". 

If the lens is not manufactured by Canon itself, ISO not be pushed secret, and the lens will appear darker than a Canon lens that had the ISO pushed.


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## AcutancePhotography (Oct 24, 2014)

NancyP said:


> The reason to buy an f/1.4 lens is to shoot at f/1.4.



I don't share this opinion. I buy a 1.4 because I want to shoot at 2.8 and have the lens sharp. If I want to shoot at 2.8 and I buy a 2.8, then I am shooting wide open and lenses don't tend to be sharpest wide open.


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## infared (Oct 24, 2014)

ajfotofilmagem said:


> cayenne said:
> 
> 
> > However, from what I've read and saw in person, the extra special coatings on the Sigma, actually seem to make it a bit slower than 1.4. It almost seemed that it was about 3/4 of a full stop slower than the Canon.
> ...



Terrifying?... I save that adjective for things like Ebola and perhaps automatic weapons pointed at me. LOL! 8)


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## tcmatthews (Oct 24, 2014)

I am increasingly coming to the conclusion that all of the focus inconsistencies are coming from the combination of the advanced Canon focus systems (like in the 5d III) and the sigma lenses. If you look into the the Canon manuals you will notice that on some lens certain focus positions are disabled. Lens and auto focus points are grouped. I do not have a 5D III so I do not know how this affects third party lens.

It is very likely that this auto focus point information is not correctly being sent by the Sigma Art lenses to the Camera. Then when the standard AF Micro-adjustments are done in camera it just makes the situation worst.

It is very possible that the USB Dock is the only way to adjust the Art lenses consistently.

Given the state of Canon 50mm I am really considering getting a Sigma Art 50mm. So if anyone has experience regarding calibration using the USB Dock it would be appreciated.


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## NancyP (Oct 24, 2014)

A good f/2 lens will be very sharp at f/2.8. A great f/2.8 lens will be tack sharp at f/2.8 eg Zeiss 21mm f/2.8.


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## docsmith (Oct 24, 2014)

Not discounting others experiences with the 50A, just saying that my 50A AFs just fine with a 5DIII using the center point or the side points. After reading this thread, I went and tested it again, and still no more variation than any other lens.


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## ajfotofilmagem (Oct 24, 2014)

infared said:


> ajfotofilmagem said:
> 
> 
> > cayenne said:
> ...


In fact, I was terrified when I discovered that my Canon 50 F1.4 only becomes sharp and contrast when used in F2.8. I was also terrified of the price of Canon 50L with a sharpness well below that Sigma Art.


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## Eldar (Oct 24, 2014)

The Sigma 50A is an optically fantastic lens, with a very poor and unstable AF system. As I have stated in other threads, I do not understand how Sigma can push something as inconsistent as this to the market.


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## zlatko (Oct 24, 2014)

Eldar said:


> The Sigma 50A is an optically fantastic lens, with a very poor and unstable AF system. As I have stated in other threads, I do not understand how Sigma can push something as inconsistent as this to the market.



It is hard to reconcile the diverse opinions about this lens. Some people like yourself report poor & unstable AF. But reading the reviews on B&H, some seem to find the lens outstanding in every way, including AF. So many reviews absolutely glow with praise! I will have to try the 50A for myself at some point. Is it possible that some copies are truly excellent while others are defective?


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## ajfotofilmagem (Oct 24, 2014)

zlatko said:


> Eldar said:
> 
> 
> > The Sigma 50A is an optically fantastic lens, with a very poor and unstable AF system. As I have stated in other threads, I do not understand how Sigma can push something as inconsistent as this to the market.
> ...


Yes, it is possible some Sigma Art work very well and others being inconsistent. But why? I suspect that different bodies behave differently in relation to AF Sigma lenses. 

But, and tests that use 5D Mark iii successfully, and others with focus problems? I think the firmware version of the body can cause unpredictable behaviors of AF.


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## VeloDramatic (Oct 24, 2014)

drmikeinpdx said:


> Infrared and VeloDramatic... Glad you are having good luck with the 50 Art lens.
> 
> What body are you using your 50 Art on?
> 
> Do you use the outer focus points or mainly the center point?



I use the 50 Art on 1Dx, 1D4 and 5D3 bodies. When shooting everything but landscape I'm focused on dynamic composition and don't favor any focus point. As a sports shooter I'm using rear-button focus, cross-type only, often in Servo mode provided the light is decent.


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## VeloDramatic (Oct 24, 2014)

zlatko said:


> VeloDramatic said:
> 
> 
> > I just purchased the Sigma 50mm Art and without question it's a fantastic lens. It doesn't have the AF response of the 200 f2 but AF is great and the lens is exceptionally sharp. I'm just back from the Hebrides, and a landscape change of pace, where the Sigma 50 performed terrifically... including in portrait orientation with a RRS pano tripod setup for some really nice stitches.
> ...




Sure, I'll shoot below f2 if the light conditions warrant/necessitate or I'm after a particularly shallow look for a particular shot but I'm just not fixated on f1.4. I don't buy quality glass or solely judge it's performance by how it performs at the limit. I know that's not why you are asking but it's always in my thoughts when thinking about lens performance. You get people who say why would you bother spending more to buy a f1.4 lens and shoot it at f2 or f4? Answer, because it's better glass and a stop or two of performance can sometimes save your ass on a job.

I haven't seen any AF problems yet at any aperture. I have the USB dock but haven't done any additional calibration. Bodies are 1Dx, 1D4, 5D3 and 5D2. I've shot the 50 art on all four.


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## infared (Oct 24, 2014)

zlatko said:


> Eldar said:
> 
> 
> > The Sigma 50A is an optically fantastic lens, with a very poor and unstable AF system. As I have stated in other threads, I do not understand how Sigma can push something as inconsistent as this to the market.
> ...


 Yes...I got a defective one from B&H...spent a day screwing around with the Sigma Dock..etc...was making me CRAZY and I though..."why am I doing someone else's work for them??? on a $950 lens no less..."
I called B&H and told them the situation..and they were well aware of the issue..at least in a one-on-one situation and they sent me out another lens right away. It was great...just some minor little tweeks on the Sigma Dock... Works great for my needs. BTW I am running the latest version of firmware on my 5DIII....but my experience would tell me that it is a lens issue..not a firmware issue...
For how the lens WOW's me....I thought that it was certainly worth the hassel. ...and let's face it..the experience that I had is total bull shit! LOL!


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## StudentOfLight (Oct 28, 2014)

Are the AF issues across the board (i.e. with all bodies) or does it only happen with the 61pt AF system bodies? 

For example, my Tamron 24-70 VC does not work well with the 5D-III but works fine with my 6D and 1Ds-III. So does the Sigma lens have a compatibility issue with the 61pt AF system or is it just completely unreliable due to some design issue (e.g. excessive slop in AF gearing or field curvature etc...) ???


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## Ripley (Oct 29, 2014)

StudentOfLight said:


> Are the AF issues across the board (i.e. with all bodies) or does it only happen with the 61pt AF system bodies?
> 
> For example, my Tamron 24-70 VC does not work well with the 5D-III but works fine with my 6D and 1Ds-III. So does the Sigma lens have a compatibility issue with the 61pt AF system or is it just completely unreliable due to some design issue (e.g. excessive slop in AF gearing or field curvature etc...) ???



I can't comment on your question directly because I only have one camera body. However, looking back at the shoots I did while I had this lens I'm noticing something... it only front focused in the low light situations but all of the daytime shots look spot on.

The focus ring on the copy I rented was tightly assembled... stiffer than either of my f2.8 zooms. I know that doesn't necessarily correlate to AF performance, but thought someone might care to know.


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