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Author Topic: 6D autofocus capabilites: let's bust some myths about it  (Read 65686 times)

Pi

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Re: 6D autofocus capabilites: let's bust some myths about it
« Reply #15 on: November 04, 2013, 08:22:47 AM »
Focus and recompose leads to back focusing if the plane of focus is really a plane. The problem is most noticeable, roughly speaking, with wide primes focused far off center, with a subject close to you. Then you can use the outer points. In good to moderate light, they focus reliably even on my lowly 5D2 with, say, the 50L or the 35L. I still focus and recompose even with those points. In really low light, I would not use them.

About cross or not cross type - the proof is in the pudding. It just works, at least in most cases.
« Last Edit: November 05, 2013, 06:47:02 PM by Pi »

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Re: 6D autofocus capabilites: let's bust some myths about it
« Reply #15 on: November 04, 2013, 08:22:47 AM »

Chosenbydestiny

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Re: 6D autofocus capabilites: let's bust some myths about it
« Reply #16 on: November 04, 2013, 08:34:22 AM »
A friend and I were shooting a model's headshots side by side a couple of days ago at his home studio. He had his 5D Mark III with 70-200mm f/2.8L IS mark 1, and I was using a 6D with 70-200mm f/4L IS. I had zero trouble focusing, but there were a couple of times where the model had to wait for him because he couldn't land focus for some reason. We were both using center point in one shot mode. I am not, in any way, saying the 6D is a better camera. But in that particular situation my center point did great. In fact, I still haven't found a normal situation where I couldn't focus. Then again, I rarely use the outer points on 6D which I do feel are better on my 5D mark IIIs that I use at work. They really are two different bodies for different audiences, but the 6D can pull it's weight in almost every situation that the 5D mark III can and sometimes it actually does better.
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neuroanatomist

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Re: 6D autofocus capabilites: let's bust some myths about it
« Reply #17 on: November 04, 2013, 08:39:28 AM »
Regarding 1Dx and 5DIII, I thought that they had the same AF system, which was probably the biggest plus of the 5DIII.

They are nearly the same.  The difference is that the 1D X AF system receives information from gets its more sophisticated metering sensor, which allows it to perform face recognition and tracking during phase AF.
EOS 1D X, EOS M, and lots of lenses
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bchernicoff

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Re: 6D autofocus capabilites: let's bust some myths about it
« Reply #18 on: November 04, 2013, 10:50:09 AM »
I've had the Mk III since it launched and received a 6D on Friday. I took it on a hike yesterday with the Sigma 35 and Canon 50 1.2. I used both the center point focus recompose technique and the farthest outside point. We got in late last night and I only glanced through the images after importing, but my initial impression was that focus accuracy was fine. I didn't bring the Mk III or do a side-by-side comparison though.

I will comment that I am surprised by how much lighter and more compact the 6D feels. It feels like more of a joy to take out and shoot than the Mk III which sometimes seems like a burden. I plan to sell the Mk III.

I'll do some editing tonight and post some of the images.
6D, Fuji X-T1, X-E1
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Ruined

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Re: 6D autofocus capabilites: let's bust some myths about it
« Reply #19 on: November 04, 2013, 11:37:40 AM »
There is no doubt the 5DMKIII autofocus technically murders the autofocus on the 6D.

But, a similar autofocus system to the 6D (in fact very slightly worse) was in the 5D and 5D MKII - both of which produced tons of stunning pictures over the years.

Will the 6D require somewhat more skill and planning to get the shots you want compared to a 5D MKIII?  Yes.  Is it insurmountable?  No.  If you have the money and want to spend it, by all means the 5DMKIII is a better camera with better autofocus.  But if you are at all budget limited, the autofocus system of the 6D is not a deal breaker for many popular types of photography.  Just don't expect it to be a sports camera.
« Last Edit: November 04, 2013, 11:46:34 AM by Ruined »

sdsr

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Re: 6D autofocus capabilites: let's bust some myths about it
« Reply #20 on: November 04, 2013, 11:51:15 AM »
Well, the 6D has what is effectively a 1-point AF system.

A bit of an exaggeration...  I often use the outer focal points on my 6D.  Yes, the center point is much better, but the outer points are not bad in decent light.  I can nail shallow DOF with the outer points.

I bought a 5DIII after I had owned a 6D (and 5DII) and can't say I noticed much better accuracy in very low light comparing the 6D and 5DIII (I'm referring to static subjects; I hardly ever shoot anything else).  What is nice, though, is having far more AF points to work with.  Too bad they don't cover a larger area on the viewfinder (it's rather a shock switching from my OM-D, with its (highly accurate) focus points over almost all the image area, back to a FF dslr - doesn't matter which - with the small area of AF coverage).  During the week I rented a Sigma 35mm 1.4 I had no problems with it on the 6D (didn't yet have a 5DIII), though of course a week hardly allows for thorough testing.

If the OP is really concerned about the performance of the 6D with one of the lenses mentioned, why not rent one and find out first hand (assuming you live somewhere where that's an option)?

Lamora

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Re: 6D autofocus capabilites: let's bust some myths about it
« Reply #21 on: November 04, 2013, 01:39:56 PM »
If you buy the 85mm 1.2L you use it to shoot wide open. A 6D will not make you happy as focus recompose doesn't work that well at f1.2 at close to medium working distances.

The main reason I upgraded to the mark iii was the better spread of AF points. I'm happy I did as using the correct AF points as opposed to focus recompose resulted in way more pictures with accurate focus.

Buy the mark iii and you will be happy. Buy the 6d and you will want to upgrade later.

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Re: 6D autofocus capabilites: let's bust some myths about it
« Reply #21 on: November 04, 2013, 01:39:56 PM »

Marsu42

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Re: 6D autofocus capabilites: let's bust some myths about it
« Reply #22 on: November 05, 2013, 02:16:52 AM »
Will the 6D require somewhat more skill and planning to get the shots you want compared to a 5D MKIII?  Yes.

You're talking of focus & recompose skill with thin dof, I guess?

One thing I'm experiencing with my 100L and the 6D and I have "learned" to circumvent by taking more frames is that the 6D sometimes produces actual af misses, i.e. the focus is completely elsewhere even though the camera did an af confirm (red dot) - I practically never experience this with my 6d af, though the 60d more often has "micro misses" while the 6d is either spot-on or lost in the woods.

thgmuffin

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Re: 6D autofocus capabilites: let's bust some myths about it
« Reply #23 on: November 05, 2013, 04:15:50 AM »
Focusing and recomposing wide open doesn't shift the plane of focus? I'm a bit confused on this one...

candc

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Re: 6D autofocus capabilites: let's bust some myths about it
« Reply #24 on: November 05, 2013, 06:17:36 AM »
there is a small amount of focus shift due to field curvature. the sensor is flat and not curved like our retinas so something in focus at the sensor center will be slightly front focused at the edges. not a big deal in most cases but with a super shallow dof it could be
« Last Edit: November 05, 2013, 06:19:40 AM by candc »

gigabellone

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Re: 6D autofocus capabilites: let's bust some myths about it
« Reply #25 on: November 09, 2013, 05:04:05 AM »
After a lot more reading of both technical reviews and users' opinions, i'm starting to have doubts about my lens choice. I'm considering 2 cheap but good lenses, the 35/2 IS and the 85/1.8. Since DoF will be larger, will i have a higher chance of accurate focus on a 6D?
6D, Sigma 35/1.4, 85/1.8, YN560III

BL

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Re: 6D autofocus capabilites: let's bust some myths about it
« Reply #26 on: November 09, 2013, 05:24:00 AM »
focus recompose with the 85 L @ 1.2, regardless of your AF system, will prove to be frustrating at best. 

If you're going to shoot the 85L wide open with the 6D, just use the center point and crop for the proper orientation in post.
M, 5Dc, 1Dx, some lenses, a few lights

bholliman

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Re: 6D autofocus capabilites: let's bust some myths about it
« Reply #27 on: November 09, 2013, 05:25:45 AM »
After a lot more reading of both technical reviews and users' opinions, i'm starting to have doubts about my lens choice. I'm considering 2 cheap but good lenses, the 35/2 IS and the 85/1.8. Since DoF will be larger, will i have a higher chance of accurate focus on a 6D?

I enjoy shallow depth of field photography, but try to keep enough DOF so I can keep both of my subjects eyes and entire face in focus.  That means stepping down a little with fast primes, our in your case could mean buying lenses with a smaller maximum aperture.  The additional DOF also gives you some latitude if your focus is off a little.

The 35/2 IS and 85 1.8 are excellent lenses.  If you don't have the funds for the Sigma 35 and 85 1.2, these are great alternatives.  Even if you do have the funds, it may still be a good decision.  The more expensive lenses advantages may not be worth the additional $$$ to you.  One bonus:  The 85 1.8 autofocuses much faster than the 85 1.2!
« Last Edit: November 09, 2013, 05:40:42 AM by bholliman »
Bodies:  6D, EOS-M
EF Lenses: 35mm f/2.0 IS, 100mm f/2.8L IS Macro, 135mm f/2.0L, 16-35mm f/4L IS, 24-70mm f/2.8L II, 70-200mm f/2.8L IS II; EF-M Lenses: 22 f/2, 18-55
Speedlites: ST-E3-RT, 600EX-RT (x3)

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Re: 6D autofocus capabilites: let's bust some myths about it
« Reply #27 on: November 09, 2013, 05:25:45 AM »

BL

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Re: 6D autofocus capabilites: let's bust some myths about it
« Reply #28 on: November 09, 2013, 06:01:30 AM »
true that, but when you hit it on the head @ 1.2, it's sublime

proper DOF at 1.2 with any sort of consistency takes A LOT of practice, and for me that's meant relying less on AF and pushing my eyeball mk I's to the limit :P
M, 5Dc, 1Dx, some lenses, a few lights

Dylan777

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Re: 6D autofocus capabilites: let's bust some myths about it
« Reply #29 on: November 09, 2013, 09:08:07 AM »
After a lot more reading of both technical reviews and users' opinions, i'm starting to have doubts about my lens choice. I'm considering 2 cheap but good lenses, the 35/2 IS and the 85/1.8. Since DoF will be larger, will i have a higher chance of accurate focus on a 6D?

Get a 5D III. I see your case on this forum quite often. 6D sounds great from the begining due to lower price tag. Once the camera is in your hand and crappy AF becomes crappy, then you wish I have purchased 5D III. Keep in mind, 5D III has DUAL-CROSS type in center, therefore, it helps a lot with large prime(50L, 85L II).
Same thing for those bought 24-105, they thought the lens is "good enough" until they hand on 24-70 II.

Get better gear if you can afford it. It will save you a lot of time and money in the long run.

Here are some photos 85L II + 5D III,  jpegs straight from camera, zero PP: http://albums.phanfare.com/isolated/oerWLRdp/1/6253867

In term of lenses, 85L II is an EXCELLENT lens for portrait. There is no other 85mm out there can really out perform 85L II @ $2000ish. If you want fast AF with decent bokeh, then get 135L.
« Last Edit: November 09, 2013, 09:12:58 AM by Dylan777 »
Bodies: 1DX -- 5D III
Zooms: 16-35L f4 IS -- 24-70L II -- 70-200L f2.8 IS II
Primes: 40mm -- 85L II -- 135L -- 200L f2 IS -- 400L f2.8 IS II

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Re: 6D autofocus capabilites: let's bust some myths about it
« Reply #29 on: November 09, 2013, 09:08:07 AM »