# Lenstip review of Canon 85mm 1.4 L



## Chaitanya (Mar 18, 2018)

Here is link to lenstips review of Canon 85mm 1.4L
https://www.lenstip.com/index.php?test=obiektywu&test_ob=526


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## ahsanford (Mar 18, 2018)

_"Such a performance would be very favourable for the Canon but the positive image is destroyed by the Sigma A 85 mm f/1.4 DG HSM. The Sigma is cheaper than the Canon but its performance is better both at the maximum relative aperture and on stopping down."_

Elsewhere, they rate a 'Pro' as "lack of any serious problems with distortion" yet in 'Con' they have "distortion level higher than that of direct rivals". Really?

And then they drop _this _whammy on it:

_"39% of shots were beyond reproach so their MTFs didn’t differ from the maximum results by more than 10%. Fully acceptable photos, so those which MTFs were within 80-90% of the maximum results constituted 29% of the whole. There were as much as 30% of slightly out-of-focus photos (with MTFs ranging from 70 to 80% of the maximum value) and 2% of all shots were complete misses (with MTFs worse than 70% of the maximum resolution). This is not a performance you would expect from an expensive L-series instrument."_

...which is absolutely not the experience of this forum (from my reading) and my week-long rental -- AT ALL. The 85 f/1.4L IS had an absolutely superlative AF setup in my hands: perhaps not the fastest USM on the planet but absolutely take-it-to-the-bank consistent, even at wide apertures. I have no idea how LT got this result without having been given a poor copy.

Oh, and by the way, despite that relatively abysmal AF test reported above... it still wasn't rated as a 'Con' in their summary. :

- A


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## arthurbikemad (Mar 18, 2018)

The Sigma may be great, but for me as someone who was burned by Sigma years ago I will never buy another no matter how good!


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## AlanF (Mar 18, 2018)

Lenstip can be quite erratic in their reviews, sometimes astonishingly so. I find ePhotozine and Trusted Reviews to be more towards the consensus in general, and they have a much higher regard for the Canon 85/1.4.

https://www.ephotozine.com/article/canon-ef-85mm-f-1-4l-is-usm-review-31800
Fast and accurate AF

http://www.trustedreviews.com/reviews/canon-ef-85mm-f1-4l-usm
The distinct advantage it has over lenses such as the Sigma 85mm f/1.4 Art DG HSM .... is the way it offers unparalleled stability thanks to its optical image stabilisation that’s effective to 4 stops

The real beauty of this lens is that I found my hit-rate of pin-sharp shots at f/1.4 much higher than using the EF 85mm f/1.2 L II USM


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## Larsskv (Mar 18, 2018)

My experience with the AF on the 85 f1.4 L and 1DXII, is fantastic. My hit rate is better than with any other prime lens I’ve used, both for still and moving subjects. I cannot give a scientific number, but if the hit rate is below 98%, I would be surprised.


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## slclick (Mar 18, 2018)

It read like a Petapixel review.


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## Viggo (Mar 18, 2018)

Well, they obviously didn’t find it that great.

And I must say, hard as it is, I agree with the distortion levels, it shows too much pincushion distortion...

... and, unfortunately, I have to agree 100% with the AF performance. I have to overshoot, and I get more than 2% WAY oof shots without any reason... I can shoot a portrait in super lightning conditions and have every other shot miss with every other spot on. I thought there might be something wrong with the camera, mounted the 35 L II and it just can’t miss anything. And just to be clear, it doesn’t have anything to do with more dof..


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## jaell (Mar 18, 2018)

I'm getting mixed results. I'll shoot a burst of shots on a still subject, with a high shutter speed, and in DPP the AF point is the same in all the shots, but up to 1/3 of the shots in the burst will drift to back focus.

I'm going to have to do some AFMA to rule out just back focus issues. It's just weird when I take 3 shots in a row, with the first and third focusing right where I want, and the send focusing maybe a half inch further away--and the subject hasn't moved, and I'm shooting at 1/100th or faster, so the three shots are completed in maybe 1/3rd of a second, with the IS on, and a non-moving subject.

The shots that are on are sharp as a tack, though.


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## YuengLinger (Mar 19, 2018)

jaell said:


> I'm getting mixed results. I'll shoot a burst of shots on a still subject, with a high shutter speed, and in DPP the AF point is the same in all the shots, but up to 1/3 of the shots in the burst will drift to back focus.
> 
> I'm going to have to do some AFMA to rule out just back focus issues. It's just weird when I take 3 shots in a row, with the first and third focusing right where I want, and the send focusing maybe a half inch further away--and the subject hasn't moved, and I'm shooting at 1/100th or faster, so the three shots are completed in maybe 1/3rd of a second, with the IS on, and a non-moving subject.
> 
> The shots that are on are sharp as a tack, though.



I was having almost exactly the same type of trouble but I've reduced the focus problems by being much more mindful of my finger slightly moving the focus ring. While overall the ergonomics are much better then the 1.2 II, at least on that older model we could disable the focus ring all together.

The AF on the 1.4 IS does not compare well to zooms such as the 24-70 F2.8 or the 70-200 F2.8 in my opinion. I think I'm a little disappointed by the performance of outer AF points. But reviews by TDP and Dustin Abbott alerted buyers to the fair to middling AF. This is by no means a sports lens or one that is ideal for fast action events.

I'm not sure that the AF mechanisms in the lens can keep up with AI servo on the 5D IV, and it does show in the keeper percentage.

I'm afraid that one negative effect of competing with Sigma is an effort to reach a price point that sacrifices excellence.


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## arthurbikemad (Mar 19, 2018)

I really wanted to hear great things about this lens, I sold my 1.2II in the hope the new 1.4 would be stellar, reading though right now I was half way through dialing up sales to buy one now its finally in stock here in the UK, the last straw for me with my 1.2II was a few weeks back shooting some static bikes with lots of blue, the fringing was so bad upon removal I was eating away blue from the subject to remove it, I decided the time had come to sell it on even though it's given me some classic portraits of my little girl. I think for now I will stick with my 24-70II and 70-200II and just live with f/2.8 and the rendering, perhaps I have been spoilt with the new 35/1.4 and it's truly wonderful characteristics, the new 35 defiantly has the magic, shame the 85 has some negative press so far.


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## Ian_of_glos (Mar 19, 2018)

arthurbikemad said:


> I really wanted to hear great things about this lens, I sold my 1.2II in the hope the new 1.4 would be stellar, reading though right now I was half way through dialing up sales to buy one now its finally in stock here in the UK, the last straw for me with my 1.2II was a few weeks back shooting some static bikes with lots of blue, the fringing was so bad upon removal I was eating away blue from the subject to remove it, I decided the time had come to sell it on even though it's given me some classic portraits of my little girl. I think for now I will stick with my 24-70II and 70-200II and just live with f/2.8 and the rendering, perhaps I have been spoilt with the new 35/1.4 and it's truly wonderful characteristics, the new 35 defiantly has the magic, shame the 85 has some negative press so far.


I am not sure that reviews are really all that helpful. They seem to dwell on obscure, technical definitions of image quality such as MTF charts rather than the talking about the usability of the lens or whether the it is capable of producing pictures that will sell. 
Regarding the Canon 85mm F1.4, now the price has fallen slightly I have decided to buy one but before I sell my 85mm F1.2ii I plan to do some comparisons between the two lenses, and also the 135mm F2 which is another lens I use for portrait work. If you promise not to laugh I will show you the results side by side so you can see for yourself what the differences are. I am not expecting the F1.4 to be significantly better than the F1.2, and in fact the main reasons why I bought it were for the better weather sealing (so I can use it outside), the faster autofocus so I can shoot moving subjects, and the image stabilisation so I can continue to take pictures even when I have a particularly bad hangover.
I agree with you about the 35mm F1.4 by the way - my best lens by some distance.


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## Random Orbits (Mar 19, 2018)

I think I've been spoiled by the superlative AF performance of the 35L II and the 24-70 f/2.8 II. With those lenses, I leave the camera in servo AF and use BBF exclusively. With the the 85L f/1.4 IS, the accuracy isn't as good for static subjects with servo. I can see/hear the camera (5D4) dithering/micro hunting even when the subject isn't moving. I might have to try it in one shot for portraits instead or take a burst. Hopefully this will be addressed with a firmware update.

What I was surprised with was how WELL it worked for a girls basketball game shooting wide open. The keeper rate was lower than the 24-70 f/2.8 II but it didn't feel that much lower even though the DOF was much thinner. For sports, I use single AF point only and move it around with the joystick as needed, but it's never in the center. The look with the shallow DOF is definitely a plus in this case -- gyms are ugly.


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## Ian_of_glos (Mar 19, 2018)

Random Orbits said:


> I think I've been spoiled by the superlative AF performance of the 35L II and the 24-70 f/2.8 II. With those lenses, I leave the camera in servo AF and use BBF exclusively. With the the 85L f/1.4 IS, the accuracy isn't as good for static subjects with servo. I can see/hear the camera (5D4) dithering/micro hunting even when the subject isn't moving. I might have to try it in one shot for portraits instead or take a burst. Hopefully this will be addressed with a firmware update.
> 
> What I was surprised with was how WELL it worked for a girls basketball game shooting wide open. The keeper rate was lower than the 24-70 f/2.8 II but it didn't feel that much lower even though the DOF was much thinner. For sports, I use single AF point only and move it around with the joystick as needed, but it's never in the center. The look with the shallow DOF is definitely a plus in this case -- gyms are ugly.



Most of the time I would expect the 35mm F1.4 or the 24-70 F2.8 to exhibit greater depth of field than the 85mm F1.4 - so the 85mm the lens would try and adjust focus even if your subject only moved very slightly. This might explain the hunting that you are seeing, but it is a characteristic of the focal length and the aperture not this particular lens.
I am amazed that you are able to keep a single AF point positioned over the action with a fast moving sport such as basket ball. I need to use zone AF to keep my AF point positioned in approximately the right place but I also need to stop down a little to increase my chances of having enough of the action in focus.
I must admit that I had not considered using my 85mm F1.4 for sport, but now I am keen to try it out to see how it performs.


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## ahsanford (Mar 19, 2018)

Really surprised to hear these comments -- thanks for sharing. 

With WA primes, I'm almost always shooting One Shot AF in non-burst situations, so that may explain my (effectively perfect) AF experience with that lens. But I was using off-center AF points for sure, and they worked perfectly.

- A


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## Larsskv (Mar 19, 2018)

ahsanford said:


> Really surprised to hear these comments -- thanks for sharing.
> 
> With WA primes, I'm almost always shooting One Shot AF in non-burst situations, so that may explain my (effectively perfect) AF experience with that lens. But I was using off-center AF points for sure, and they worked perfectly.
> 
> - A



I am surprised as well. I use both One shot and servo AF, and off center points as well. For the most I one focus point at the time, and as I said, the 85f1.4 L IS works better for me than the 35L II.


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## Random Orbits (Mar 19, 2018)

Ian_of_glos said:


> Random Orbits said:
> 
> 
> > I think I've been spoiled by the superlative AF performance of the 35L II and the 24-70 f/2.8 II. With those lenses, I leave the camera in servo AF and use BBF exclusively. With the the 85L f/1.4 IS, the accuracy isn't as good for static subjects with servo. I can see/hear the camera (5D4) dithering/micro hunting even when the subject isn't moving. I might have to try it in one shot for portraits instead or take a burst. Hopefully this will be addressed with a firmware update.
> ...



You'll have to let us know whether or not you're finding some type of AF hunting/inconsistency that Viggo and I are seeing in AF servo when you get your copy in. I don't recall having the issue with the 85L II -- that is a ponderously slow lens but it is accurate. Again, I'm not having a problem in AI servo when the subject is moving, and perhaps that's because I'm expecting missed shots from time to time, but I was satisfied with the keeper rate with moving subjects.

I link the AF point to camera orientation, and pictures of offense are better than defense so the AF point doesn't have to be adjusted that quickly often. Landscape orientation when the players are crossing the court and then portrait orientation when there's a shot on the basket. I'm dealing with 8 year olds, so it's not super fast, but they are smaller subjects.  I've never really tried zone AF much... I find it easier to select the AF point manually and pan especially in team sports where there are other players passing in front of my subject in the frame.


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## Ian_of_glos (Mar 19, 2018)

Random Orbits said:


> Ian_of_glos said:
> 
> 
> > Random Orbits said:
> ...


Well to be honest I bought the lens yesterday, but today has been so busy I have not even had time to take it out of its box yet. 
When I tried it in in the shop the autofocus seemed to be very quick and responsive, but none of the subjects were moving and it is not something I tested as I had not even considered using it for sports/action. However, as soon as I can I will ask the children to burn off some of their excess energy and see whether it exhibits the hunting behaviour that you and Viggo describe. It will be an interesting test.
Also I am planning to see how it performs in comparison to the 85mm F1.2 and the 135mm F2 for portrait and still life. I will pick some subjects that are likely to show chromatic aberration to see if it is an improvement on the F1.2.
The thought of using the 85mm F1.2 on AI Servo amused me as I am more used to telling my models to sit absolutely still when I use this lens and I have only ever used it on One Shot.


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## Viggo (Mar 19, 2018)

Will be interesting to see more people’s experience for sure!

I must clearify, mine doesn’t hunt, there’s no way of telling when shooting that it suddenly misses. I focuses quick and locks, I take the shot and it’s way off.

But, keep in mind, this isn’t like the Sigmas I used to own, and that most of you have read about, lol. I would say it works quite well, but I’m not used to having shots missed completely, the good thing is that in a burst where it misses the very next shot is sharp. Expect some weird misses and less great hitrate, but it’s better than the 1.8 and the 50 L. 

Another point is that I, personally, only use Ai Servo

I don’t expect it being a faulty lens or camera, I just expected better, it being a new L and so on. Still my most used lens.


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## YuengLinger (Mar 19, 2018)

Viggo said:


> Will be interesting to see more people’s experience for sure!
> 
> I must clearify, mine doesn’t hunt, there’s no way of telling when shooting that it suddenly misses. I focuses quick and locks, I take the shot and it’s way off.
> 
> ...



I'm finding similar strange out of focus captures within a series whether I'm using one shot or AI servo. And, same as you, I am not experiencing hunting. Just one or two completely out of focus within a sequence of 5 or 7 that are in focus otherwise. But, to repeat, my keeper rate has gone up since being more careful about my finger touching the focus ring. And it seems like I'm doing a little better again after glowing clean the sensor area.


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## hne (Mar 20, 2018)

Viggo said:


> I must clearify, mine doesn’t hunt, there’s no way of telling when shooting that it suddenly misses. I focuses quick and locks, I take the shot and it’s way off.



Mine doesn't hunt either, unless trying to focus on a small patch of texture-less something barely blocking the sun. Though sometimes, my camera tries to acquire focus on something totally different when subject tracking fails. It usually succeeds, generally on something in the far background.

There are some cases where I believe my spot AF single point slides off the target and the lens has to do a large shuffling of glass causing the next image in a burst to be out of focus, but that is rare and generally doesn't happen in subject tracking mode. Also mostly seems to happen in burst mode.



Viggo said:


> Another point is that I, personally, only use Ai Servo
> 
> I don’t expect it being a faulty lens or camera, I just expected better, it being a new L and so on. Still my most used lens.



I also only use Ai Servo. Previously I always had either One-Shot or Ai Focus, but between the extreme shallow DOF and the absurdly slow shutter speeds possible with 85/1.4L IS I couldn't get more enough shots in focus even holding my breath.

It's my second most used lens, after the 35/1.4L. It is my 6th L lens. I expected worse.


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## Ian_of_glos (Mar 20, 2018)

hne said:


> Viggo said:
> 
> 
> > I must clearify, mine doesn’t hunt, there’s no way of telling when shooting that it suddenly misses. I focuses quick and locks, I take the shot and it’s way off.
> ...



I will not be able to test mine until the weekend, but what I plan to do is this:
Arrange for my subject to run towards the camera and shoot using my 5D mark 4's max burst rate of 7fps and AI servo, firstly at the maximum aperture of F1.4 and then at F5.6 as this is an aperture that I would often use for sports. I am expecting a higher keeper rate at F5.6 than at F1.4 but let's see what happens. The camera does predict the focus point for moving subjects to some extent, but whether it is good enough to focus correctly within the very narrow depth of field available at F1.4 remains to be seen.
Like you I often find that the camera often locks onto something with good contrast in the background, but that is always due to my inability to keep up with a moving subject. I have found that the best remedy is to use zone AF as focus will lock onto the nearest item with acceptable contrast that it can find within the focus zone, so I don't need to be quite so precise about where I place the focus point. It is like using automatic selection AF but using only the part of the scene that I am interested in.
When I am photographing a subject where there is no contrast I use AF point expansion - so it will look for good contrast with the neighbouring AF points if it is unable to achieve focus at the first attempt.

Last night I tested the lens for the first time using a subject that was sitting watching the telly and one shot AF. It focussed correctly every time and I obtained very sharp images using an aperture of F1.4. One thing that really impressed me was the image stabilisation and I was able to obtain sharp images with no camera shake at shutter speeds as low as 1/20 - not quite the full 4 stops that Canon claim but more than good enough for anything I am ever likely to do.
Originally I was going to compare the 85mm F1.4 against the F1.2 and my trusty 135mm F2, but as so many people have reported AF problems with this lens I will do the focussing tests first.


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## alexanderferdinand (Mar 20, 2018)

First I got a Sigma 85/1,4 for testing.
IF it focused correctly, it was fine.
The issue with this lens: sometimes the Autofocus would not start. I had to give the focusring a Little Twist, then it started focusing, and was spot on. 
But sometimes it started itself- like it should.
So to wait- does it or not was very annoying and is only acceptable in steady situations. If you want to make a snapshot- good luck. Chances are good you miss the shot.

The Canon 85/1,4 IS: fast, correct, if wide open it could miss the few Millimeters that makes it very sharp, but most of the time Focus is superb.
Bokeh is also very fine and enjoyable. A fantastic lens.

Both lenses used on the 1DX MkII and 5DMkIV


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## Ian_of_glos (Mar 20, 2018)

alexanderferdinand said:


> First I got a Sigma 85/1,4 for testing.
> IF it focused correctly, it was fine.
> The issue with this lens: sometimes the Autofocus would not start. I had to give the focusring a Little Twist, then it started focusing, and was spot on.
> But sometimes it started itself- like it should.
> ...


Sounds like you might have a fault with your copy. Is it still under warranty and if so have you taken it back to the shop and explained the problem to them?
Do you see the autofocus problem with both One Shot and AI Servo?
So far I have only taken about 20 shots with mine and each time I used One Shot autofocus. It focussed accurately and instantly every time and the only shot that is not sharp is the one where I used a shutter speed of 1/13 - but what I am seeing is clearly camera shake not missed focus.


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## alexanderferdinand (Mar 22, 2018)

@ the Sigma: had it only for testing (as I wrote). My method of focusing is AI Servo with back button Focus.
Told my dealer about my experience and why I didnt buy it.
With the Canon: no Problem at all. Very lovely lens, I love the results and use it very often


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## Ian_of_glos (Mar 25, 2018)

Viggo said:


> Will be interesting to see more people’s experience for sure!
> 
> I must clearify, mine doesn’t hunt, there’s no way of telling when shooting that it suddenly misses. I focuses quick and locks, I take the shot and it’s way off.
> 
> ...


Today I tested the new Canon 85mm F1.4 on my Canon 5D mark 4 using AI servo and the high speed continuous drive mode, which allows me to shoot at up to 7 frames per second.
The primary reason for the test was to check the autofocus accuracy using AI servo to see if the lens missed focus at all and it involved photographing my daughter running towards the camera. I used Case 2 and focus priority for the first and subsequent shots and I ran the test twice - the first time using an aperture of F1.4 and the second time using an aperture of F5.6. 
The focussing was just about perfect every time, and there is only one shot in the entire sequence that is slightly soft. In this picture the string from her hood flew up in front of her face and it looks like the camera focussed on that instead of her eyes. 
Focussing was quick and accurate and although I did not time it precisely I was able to capture 26 frames in about 4 seconds, which is very close to the maximum of 7 frames per second.
I have also taken many pictures of stationary subjects with this lens using One Shot AF and every one is sharp.
So, I am unable to explain why you have been experiencing so many focussing problems. The only thing I can think of is that the lens might be faulty or possibly the lens is not making a good electrical connection with the camera. Have you tried cleaning the electrical connections at the bottom of the lens to see if that helps?


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## Michael Clark (Mar 27, 2018)

For those having AF issues when shooting bursts of images in AI Servo:

Use some gaffer's tape to immobilize the focus ring and see what effect that has.


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## Ian_of_glos (Mar 28, 2018)

shanayabindra said:


> Awesome one. I will definitely buy one. Can anyone please tell me best website to buy this camera.


If there is a camera shop near where you live then I would always recommend trying a lens out before buying it. I bought mine from London Camera Exchange.
When I am unable to go to the shop in person for some reason, or for items such as filters, batteries and memory cards I have always found Wex Photographic to be very good.


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## YuengLinger (Mar 29, 2018)

Ian_of_glos said:


> shanayabindra said:
> 
> 
> > Awesome one. I will definitely buy one. Can anyone please tell me best website to buy this camera.
> ...



What is a "camera shop"?


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## slclick (Mar 29, 2018)

[/quote]

What is a "camera shop"?
[/quote]

Oh that was both rich and poignant


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## Ian_of_glos (Mar 30, 2018)

YuengLinger said:


> Ian_of_glos said:
> 
> 
> > shanayabindra said:
> ...


It is a shop where you buy cameras. There are a few left if you look hard enough.


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## YuengLinger (Mar 30, 2018)

Ian_of_glos said:


> YuengLinger said:
> 
> 
> > Ian_of_glos said:
> ...



In our case, if we fly far enough. :-\


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## Ian_of_glos (Mar 31, 2018)

YuengLinger said:


> Ian_of_glos said:
> 
> 
> > YuengLinger said:
> ...


Ah that is unfortunate. 
Maybe the place where you live is beautiful enough to make up for the lack of camera shops.


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## Shopbywoot (Apr 4, 2018)

Great, thanks!
https://www.ufa88.in


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## StoicalEtcher (Apr 4, 2018)

To add my experiences to those of others, I've had 85 f/1.4L IS for about 4 months now, and taken around 1,000 frames with it.

I'm loving it, and have not experienced the odd out of focus shot within a stream. Having said that, I'm mostly using it on one shot, and AI Focus , and not often using a burst of more than 3/4 shots at a time (and mostly less).

For me, it is basically nailing focus (on 5DmkIII) nearly all of the time, and when it doesn't, it is down to the focus point having not been quite where I thought I'd put it (bearing in mind it has a thin doF at 1.4-2.0)

Just wondering if some of the burst issues others are seeing might be down to IS operation on a big aperture lens not being able to keep up with AF at circa 7 fps?


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## Ian_of_glos (Apr 6, 2018)

StoicalEtcher said:


> To add my experiences to those of others, I've had 85 f/1.4L IS for about 4 months now, and taken around 1,000 frames with it.
> 
> I'm loving it, and have not experienced the odd out of focus shot within a stream. Having said that, I'm mostly using it on one shot, and AI Focus , and not often using a burst of more than 3/4 shots at a time (and mostly less).
> 
> ...


My experience is similar to yours and I only have a very few shots where the lens did not focus accurately. I shot bursts of 25-30 frames using AI Servo and it focussed quickly and accurately almost every time. In my test the subject was running towards the camera, and the only shots that are out of focus are right at the start of the sequence when my subject is furthest away. I just watched Dustin's video and his experience is the same - there are a few out of focus shots when the runner is far away but as the runner approaches the camera every shot is focussed correctly.
Incidentally a lens with a wide maximum aperture (such as the 85mm F1.4L) will be able to focus more easily and more accurately than a lens with a small maximum aperture. In fact some of my focus points are not available at all if my lens has a small maximum aperture or they change from being cross type to only being sensitive to horizontal lines.


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## Sporgon (Apr 6, 2018)

Ian_of_glos said:


> Incidentally a lens with a wide maximum aperture (such as the 85mm F1.4L) will be able to focus more easily and more accurately than a lens with a small maximum aperture. In fact some of my focus points are not available at all if my lens has a small maximum aperture or they change from being cross type to only being sensitive to horizontal lines.



Actually I don't think you are correct here; certainly my experience is that really fast lenses aren't the best for accurate focusing, especially when tracking. I have found that the best ones are high quality ( i.e. L) lenses with an aperture of f/2.8, and I believe the reason is twofold. Firstly as you say, lenses of f/2.8 and faster activate and utilise the more precise AF sensors, but secondly those high quality f/2.8 lenses are considerably sharper with less spherical aberrations wide open than say an f/1.4 lens at 1.4, so the phase detect AF has more defined contrast and definition to work with. For instance using Lenstip results the Canon 85/1.4 has an MTF50 of around 33 at f/1.4, the 70-200/2.8 IS II is in the 44 region, and of course we are all using open aperture focusing nowadays. There's also the issue of spherical aberration causing focus shift though it seems the 85/1.4 doesn't really suffer from this in practice.


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## Ian_of_glos (Apr 6, 2018)

Sporgon said:


> Ian_of_glos said:
> 
> 
> > Incidentally a lens with a wide maximum aperture (such as the 85mm F1.4L) will be able to focus more easily and more accurately than a lens with a small maximum aperture. In fact some of my focus points are not available at all if my lens has a small maximum aperture or they change from being cross type to only being sensitive to horizontal lines.
> ...


Thank you - I did not know that and I have always assumed that lenses with a max aperture of F2.8 or wider would be the best at focussing because they can make use of all the focus points, especially the cross type and dual cross type points. Certainly those lenses with relatively small maximum apertures like F5.6 tend to be the ones that hunt and struggle to find focus. However it is interesting to learn that there are some other factors that come into play.


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## Talys (Apr 6, 2018)

Ian_of_glos said:


> My experience is similar to yours and I only have a very few shots where the lens did not focus accurately. I shot bursts of 25-30 frames using AI Servo and it focussed quickly and accurately almost every time. In my test the subject was running towards the camera, and the only shots that are out of focus are right at the start of the sequence when my subject is furthest away. I just watched Dustin's video and his experience is the same - there are a few out of focus shots when the runner is far away but as the runner approaches the camera every shot is focussed correctly.



My copy is also superb in consistency and accuracy, although i don't use it for action at all.

I think the autofocus is very fast, certainly snappy enough to keep me happy, though not among the fastest of Canon lenses.


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