# 6D- Focusing



## abcde12345 (Feb 1, 2016)

Dear all,

I have been using 6D for quite a while now. I pair it with the 135mm F2 L USM lens. I use the center AF point all the time. I also set it so I use the back button focus technique. However, I realize using this technique, my focusing seems to be rather inaccurate to speak - like I will focus on the eyes, move slightly for framing, take a shot and to my dismay it focuses on spectacles or whatsoever. Is this the right technique to use, or should I use a different (limited) AF point to focus, and not to reframe my shot?


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## Mt Spokane Photography (Feb 1, 2016)

Focus and recompose when done at wide apertures can cause errors in focus. When you move the camera, the distance changes. You are also likely moving back and forth a little when you swing the camera.

This is a technique that lots of people use, and a few do well, but many have the expected focus issues.

The solution is to use small apertures like f/8. Handholding a camera, locking focus and then moving the camera is going to cause focus issues.


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## abcde12345 (Feb 1, 2016)

Definitely true for small aperture. However, issue is I would love to take my portraits at F2 (biggest aperture), which is the very reason I got it at the first place. Any recommendation in terms of handheld, quick shot technique to get most out of autofocus?


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## Gnocchi (Feb 1, 2016)

abcde12345 said:


> Dear all,
> 
> I have been using 6D for quite a while now. I pair it with the 135mm F2 L USM lens. I use the center AF point all the time. I also set it so I use the back button focus technique. However, I realize using this technique, my focusing seems to be rather inaccurate to speak - like I will focus on the eyes, move slightly for framing, take a shot and to my dismay it focuses on spectacles or whatsoever. Is this the right technique to use, or should I use a different (limited) AF point to focus, and not to reframe my shot?


Have you calibrated the lens with the body (mfa) ?
Thin dof, you move, model moves, it's a tricky technique.
Maybe the spectacles could be hindering the focus, but yeah focus recompose method does take some practicing with narrow dof.
Keep at it, you are wary of it so you just have to problem solve it.


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## Rahul (Feb 1, 2016)

abcde12345 said:


> Dear all,
> 
> I have been using 6D for quite a while now. I pair it with the 135mm F2 L USM lens. I use the center AF point all the time. I also set it so I use the back button focus technique. However, I realize using this technique, my focusing seems to be rather inaccurate to speak - like I will focus on the eyes, move slightly for framing, take a shot and to my dismay it focuses on spectacles or whatsoever. Is this the right technique to use, or should I use a different (limited) AF point to focus, and not to reframe my shot?



My suggestions - 

1) The best technique based solution would be to use the outer focus points - they work fine;
2) Try AFMA

For me the focus and recompose works reasonably well with the 6D + 135L combo. For a typical head and shoulders / tight portrait shot, the camera movement after focusing with the center point is not large and leads to lesser focusing problems as compared to, say using a 50L or the 85L on the 6D.


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## Zv (Feb 1, 2016)

I have this combo and I do at times notice inaccurate focus using focus recompose method. I chalk it down to user error. 

Like others have said first thing to do is AFMA. Run Focal several times at a distance you regularly use the lens at. note that this only really applies to wide open apertures. At narrower apertures the dof should cover any minor errors. 

The other issue is that the center AF focus point is quite large and it tends to cover more than just the eye, which is recessed in the eye socket and so the camera thinks the outline of the spectacles is what you want to focus on. I really wish the 6D had spot focus. 

You could try telling the person to briefly remove the spectacles, then focus and then have them put their spectacles back on. Seems like a hassle though. 

If you know that the camera consistently front focuses in this situation you could manually refine it with a slight touch to the focus ring in the appropriate direction. Though the amount would likely be too small to be practical. 

Personally I would just shoot at f/2.8 or narrower instead of f/2. The dof is razor thin and even a minuscule movement on your or the subjects part will result in oof shots. (For reference at 3 meters, f/2 135mm the dof is about 6cm and the area of sharp focus will be even less).


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## abcde12345 (Feb 1, 2016)

Thanks all. I have indeed done AFMA on it, hence the disappointment. The lens look sharp on LCD, (like usual), but once you try 50% view on it you realize the focus is entirely off. I think the issue with center focus point being too big could be an issue here. However, seems that everyone still think that using center AF point and reframing is still my best option?


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## Zv (Feb 1, 2016)

abcde12345 said:


> Thanks all. I have indeed done AFMA on it, hence the disappointment. The lens look sharp on LCD, (like usual), but once you try 50% view on it you realize the focus is entirely off. I think the issue with center focus point being too big could be an issue here. However, seems that everyone still think that using center AF point and reframing is still my best option?



You could use the AF point that is closest to the eye after composing. Another trick is to line up a focus point (any) exactly over the eye first then take the shot and recompose / reframe the image in post by cropping. Leave room for cropping when you shoot. This room would also mean you would be further away which means increase in dof and more likely the eye will be in focus. 

And take several shots, refocus a few times in between. One of those suckers will be on the money!


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## Rahul (Feb 1, 2016)

Why don't you use the outer focus points?



abcde12345 said:


> Thanks all. I have indeed done AFMA on it, hence the disappointment. The lens look sharp on LCD, (like usual), but once you try 50% view on it you realize the focus is entirely off. I think the issue with center focus point being too big could be an issue here. However, seems that everyone still think that using center AF point and reframing is still my best option?


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## rfdesigner (Feb 1, 2016)

My 6D arrived this weekend.. coming from a 30D the AF is no problem at all, outer points do work well, just not in moonlight.

In my opinion your biggest problem is not keeping still, but here are some options.

1. The two outer most focus points give you focus correct for any point ON THAT CIRCLE.. i.e. that far away from the centre point. Doesn't matter if the subject is at the top or bottom, if they're a similar distance from the centre point, use the outermost points. However try the technique on a tripod and you may well find things are a lot better than you're experiencing... see 2.

2. Practice panning the camera, try in front of a mirror where any errors are then doubled. It's a bit like golf where you need to keep your head still: learn not to sway as you're moving the camera, if you can tell the difference in focus between someone's glasses and their eyes then you need to sway less than this.

3. Get an Eg-S focus screen (but only use F2.8 or wider lenses thereafter).. then you could manually focus at any point in the field of view.

4. Use live view focussing.


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## tcmatthews (Feb 1, 2016)

My 6D would normally focus on the closest hard edge so it is focusing on the glasses when you point at the eyes. I noticed it most with birds. It would focus on the stick in front or behind 
Then there is the possibility of user error. 

I have found two possible workaround use live view in studio situations. Or focus on something that is nearly in the same plane as the eye. The ensure you have the lens stopped down just enough to get the eye in focus. Do not be afraid of the outer points I never had them let me down.


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## Luds34 (Feb 1, 2016)

Rahul said:


> Why don't you use the outer focus points?
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My personal (albeit limited) experience with the outer points on the 6D have been very hit and miss, even for still shots. So I essentially exclusively stick to the center point.


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## Luds34 (Feb 1, 2016)

rfdesigner said:


> 3. Get an Eg-S focus screen (but only use F2.8 or wider lenses thereafter).. then you could manually focus at any point in the field of view.



+1 While the focus screen is quite helpful for manually focusing, I really like it as more of a focus confirmation when shooting. If the focus misses almost at all, I can see it with the viewfinder.


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## Rahul (Feb 1, 2016)

Luds34 said:


> Rahul said:
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> > Why don't you use the outer focus points?
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That's strange. My hit rate with the outer focus points has been quite good even with the f/1.2 lenses.


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## Luds34 (Feb 1, 2016)

Rahul said:


> Luds34 said:
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In fairness, as I said, my experience has been pretty limited. It could also be with a certain lens. What really happened is that I first tried to use the outer focus points for AI Servo, tracking on the face with BBF to help keep the shot composed more so how I wanted. And the tracking doesn't work so well on the outer points and the hit rate was pretty low. Of course I was use to the 70D which tracks very well, even with f/2 type apertures.

And it's quite possible the few times I have issues with still subjects that I just had bad luck and hit non constrasty parts of the shot (although I'm typically focusing on the eye).

I've been saying to myself for a while I should spend some more time with the outer points and play around with them some more and see with a certain technique or something they work better. Of course, it is always a possibility that a number of my outer points are out of calibration from the center point or something.

Either way, that is the one "limitation" I look forward to being improved on with the 6D, even if it just gets a 7D/70D 19 point system (all cross type) I think it will be a big upgrade. Sure I'd like faster the 1/4000 shutter speed, and the 1/160th flash sync could be higher, but all those are pretty minor, just the focus system is the one that stands out a bit.


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## tcmatthews (Feb 1, 2016)

Luds34 said:


> Rahul said:
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Point taken I was assuming one-shot given the subject. The center focus point is really the only one that works well with AI Servo. I basically considered that mode useless until I bought a 7D II. It works ell with the 6D center point better than the 60D that has all cross AF points at least.


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## abcde12345 (Feb 2, 2016)

Luds34 said:


> rfdesigner said:
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> > 3. Get an Eg-S focus screen (but only use F2.8 or wider lenses thereafter).. then you could manually focus at any point in the field of view.
> ...



This sounds interesting. What's a Eg-S focus screen and is it easy to use on the run?


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## bholliman (Feb 2, 2016)

I have a 6D and 135/2 and have used them frequently for portraits, often at f/2 or f/2.2. I've had very good luck with both the center AF point and the outer points, even in marginal light. I don't often use focus/recompose since the DOF is so shallow at wide apertures. If you have already performed AFMA, and are still experiencing problems, you might consider sending your lens and body to Canon to have adjusted.


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## abcde12345 (Feb 2, 2016)

bholliman said:


> I have a 6D and 135/2 and have used them frequently for portraits, often at f/2 or f/2.2. I've had very good luck with both the center AF point and the outer points, even in marginal light. I don't often use focus/recompose since the DOF is so shallow at wide apertures. If you have already performed AFMA, and are still experiencing problems, you might consider sending your lens and body to Canon to have adjusted.



Well honestly I'm wondering if the issue lies with focusing and recomposing. It seems like most of posts are indicating that the error may lie with it...


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## rfdesigner (Feb 2, 2016)

abcde12345 said:


> Luds34 said:
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It scatters light more which means you get the benefit of the whole light cone from fast lenses, this makes the viewfinder brighter (a little) and gives you accurate DoF.

However it also means that slow lenses lose out as that same scatter reduces their light compared to the slightly see through Eg-A screen your camera came with.

http://www.bhphotovideo.com/c/product/590458-REG/Canon_3357B001_Eg_S_Super_Precision_Matte.html

Changing the screen on the fly is not a good idea.. if you use slow and fast lenses and you really really want this then either put up with a darker viewfinder on slow lenses or get a second body.


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## Luds34 (Feb 2, 2016)

rfdesigner said:


> abcde12345 said:
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Thankfully almost all my lenses are pretty fast (mostly primes). However I do have a 17-40 f/4L and the Tamron 150-600. I just put up with the darker screen.

I recommend the focus screen for anyone who is shooting fast glass, narrow DOF. It definitely is an added tool helping give that confirmation that the shot is in focus. I'm sure many others can manual focus better then I, however I've been pretty impressed with being able to nail focus even at f/1.4. Of course I rack back and forth a tiny bit at that point point of exact focus, looking to see what is the "most clear". Kind of at an eye doctor "A or B? Which is clearer?". My only regret was owning the 6D for nearly a year before swapping out the focus screen.


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## abcde12345 (Feb 3, 2016)

Luds34 said:


> rfdesigner said:
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Sounds interesting. Is it only usable for manual focusing?


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## Valvebounce (Feb 3, 2016)

Hi. 
Just a thought, have you disconnected the AF from the shutter button in the menus or did you just start to use the AF on button? 
Have you checked since AFMA if you use FoCal, I missed the "failed to restore settings" message after a flat battery during AFMA and found the AF was back on the shutter button, of course the back button still focuses so it took a moment to suss the problem. 
Can the 6D outer focus points be that bad, I was using the outer focus points on my 20D earlier to shoot bodged up wiring on a car I'm working on, (3 additional circuits all wired in red twisted and taped connections, one being for the add on radiator fan, and bundled together) black carpet, black heater box, red wires, all in the shadows under a dash. I was using a flash but the focus assist didn't appear to reach the outer points, it took 2 tries to get a lock in single shot but it did lock once I moved slightly to get an edge under the AF point. 
Also even Canon recommend not to use AI servo for static subjects in their manuals. 

Cheers, Graham. 



abcde12345 said:


> Dear all,
> 
> I have been using 6D for quite a while now. I pair it with the 135mm F2 L USM lens. I use the center AF point all the time. I also set it so I use the back button focus technique. However, I realize using this technique, my focusing seems to be rather inaccurate to speak - like I will focus on the eyes, move slightly for framing, take a shot and to my dismay it focuses on spectacles or whatsoever. Is this the right technique to use, or should I use a different (limited) AF point to focus, and not to reframe my shot?


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## abcde12345 (Feb 3, 2016)

Valvebounce said:


> Hi.
> Just a thought, have you disconnected the AF from the shutter button in the menus or did you just start to use the AF on button?
> Have you checked since AFMA if you use FoCal, I missed the "failed to restore settings" message after a flat battery during AFMA and found the AF was back on the shutter button, of course the back button still focuses so it took a moment to suss the problem.
> Can the 6D outer focus points be that bad, I was using the outer focus points on my 20D earlier to shoot bodged up wiring on a car I'm working on, (3 additional circuits all wired in red twisted and taped connections, one being for the add on radiator fan, and bundled together) black carpet, black heater box, red wires, all in the shadows under a dash. I was using a flash but the focus assist didn't appear to reach the outer points, it took 2 tries to get a lock in single shot but it did lock once I moved slightly to get an edge under the AF point.
> ...



Definitely my shutter button is not focusing. Only AF-on focus is working. It's easy for me to detect if shutter is focusing as when I lock-focus and press shutter again focus area will change. I've been only using One-Shot


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## Valvebounce (Feb 3, 2016)

Hi. 
Sorry I thought I read in one of the replies that you were using servo, it must have been someone else. 

Cheers, Graham. 



abcde12345 said:


> Valvebounce said:
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> > Hi.
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## Luds34 (Feb 10, 2016)

abcde12345 said:


> Sounds interesting. Is it only usable for manual focusing?



No, that was my point. I rarely manual focus (static macro work would be an exception). With the new focus screen I can now notice when the shot isn't in focus, aka the AF maybe missed, etc. With the standard screen, one can focus a fast prime (like my 35mm f/1.4 Art) and it could be off by a bit, but would look "good enough" or "in focus" via the viewfinder. And it wouldn't be until zooming in on the image after the fact that one could see it missed, or was a little soft. With the new viewfinder, I can now see the subtle, out of focus before taking the shot.

Does that help? Make sense? I'm sure someone can explain it more eloquently then I can.


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