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Author Topic: Canon Focus-Point Selection and Portrait Framing  (Read 5940 times)

solardarkroom.com

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Canon Focus-Point Selection and Portrait Framing
« on: July 02, 2010, 01:46:11 pm »

Ever since I started shooting headshots I've wondered if my choosing Canon (when I made the leap from CONTAX film boxes) was a mistake. I wonder what others do or if they even have the same frustration. I want to have a focus point on one of my subject's eyes but this rarely allows me much freedom in framing the shot the way I want to. Is there a reason why it's impossible to have focus points somewhere other than a diamond in the center of the frame? How about that old rule of thirds? I just did a portrait session yesterday and everything turned out fine as always but I feel like I'm just not getting used to it. If anyone has some thoughts on this I'd love to hear. At my age the eyes are liking the assistance of autofocus and I swear the viewfinder on my old CONTAX was brighter than even my 5DmkII.

David
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Ken Bennett

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Canon Focus-Point Selection and Portrait Framing
« Reply #1 on: July 02, 2010, 07:33:47 pm »

Hi, David,

Are you using the thumb button for autofocus activation? If not, you might try this. Having the camera re-focus every time one presses the shutter button is a real PITA, especially as (in your case) the focus point isn't over the subject. With the thumb button, one hits the AF button with the thumb to focus, then release the button and shoot away. You can choose a nearby focus point, or use the center point (if you aren't too close to the subject.) I generally leave the AF on "continuous" all the time.

The 1-D series cameras might be another solution. They have a 45-point AF system in an oval pattern, and the 1.3x crop means the focus pattern takes up a fairly large percentage of the viewfinder. (Note I am not talking about the 1-Ds series.) AF is fast and accurate, and the shooting speed helps with some portrait subjects.

--Ken

EDIT: when I made the switch from manual focus cameras to AF film cameras, the thumb button activation made a HUGE difference. After all, with manual focus, focusing and shooting are separate events, so this made much more sense to me.
« Last Edit: July 02, 2010, 07:35:36 pm by k bennett »
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dwdallam

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Canon Focus-Point Selection and Portrait Framing
« Reply #2 on: July 02, 2010, 09:40:17 pm »

I'm not sure I understand the problem. I think what you are saying is that you want to focus on one spot, and then keep that focus w/o the camera refocusing on a different spot. You can use the star key to disengage the auto-focus, as explained below, or you can focus and then just slide the auto focus off on the lens.

On the other hand, if you mean that the focal plane of the lens is not the same once you recompose, after you focus, there is no way to do that unless you focus manually. So if you want a particular area on the lens to be the focal point,  away from one of the diamond focus points, you'll need to focus manually.
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solardarkroom.com

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Canon Focus-Point Selection and Portrait Framing
« Reply #3 on: July 03, 2010, 05:02:15 am »

Many thanks to the 2 posters above... What I'm trying to say is that when I'm shooting portraits I want to keep one focus point on one eye. I select a single point rather than let the camera decide (otherwise I've found I get noses instead of eyes in the plane of focus). I've found this the only way to reliably get every shot in focus. Yesterday for example I shot almost 300 frames with 5 setups and every frame is in sharp focus (Yippee) but each time I did that I found the framing was a compromise to keep one of the points on the eye. I wish I had more points or that the diamond was larger. It sounds like unless I change my technique I might want to consider a different camera or both. Something to ponder: and no I've not used the thumb focus key and honestly I'm not sure what the distinction is in performance. Clearly I need to study that and get familiar. Thanks Guys!  
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dwdallam

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Canon Focus-Point Selection and Portrait Framing
« Reply #4 on: July 03, 2010, 07:16:18 am »

Quote from: solardarkroom.com
Many thanks to the 2 posters above... What I'm trying to say is that when I'm shooting portraits I want to keep one focus point on one eye. I select a single point rather than let the camera decide (otherwise I've found I get noses instead of eyes in the plane of focus). I've found this the only way to reliably get every shot in focus. Yesterday for example I shot almost 300 frames with 5 setups and every frame is in sharp focus (Yippee) but each time I did that I found the framing was a compromise to keep one of the points on the eye. I wish I had more points or that the diamond was larger. It sounds like unless I change my technique I might want to consider a different camera or both. Something to ponder: and no I've not used the thumb focus key and honestly I'm not sure what the distinction is in performance. Clearly I need to study that and get familiar. Thanks Guys!

It sounds like you want the part of the lens to focus after you recompose. If accurate, then no, you can't get anymore focus points than the diamond, even in the 1DS models. I never let the camera focus itself, as you have described, because for portraits and other focus point critical photography, it's a compromise. The compromise works wonders when you're shooting larger targets, and thus more of the target is in focus, which is a good thing (e.g., wildlife that fills 1/2 or less of the frame, or landscape).

There are ways around this. You can choose one of the focus points that gets you closer to your recompose, and then shoot wider than normal. In post, you can "recompose" where you want (since the lens is wider, or you are further away, the DoF will be deeper around the focal point). That way your target focal area stays sharp because your focal plane doesn't change much after you focus. Whenever you focus on one spot, and then tilt the lens, you just negated "some" sharpness, since a lens will be softer at its edges (unless you can focus out to the edge of the lens so you don't have to recompose "after" the focus).

If this is the problem, I have no idea how to solve that, except to employ tricks to get the image in the part of the lens where you need the focus to be sharp. At F11 this is rarely a problem,m but as you go larger, the DoF shrinks. What I do then if I still need deepper DoF is shoot further away from the subject, then crop in post.  This is my main argument for more pixels. I can't wait for the 1DS MKIV, if it does indeed have 32MPs, for that very reason.
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Ken Bennett

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Canon Focus-Point Selection and Portrait Framing
« Reply #5 on: July 03, 2010, 08:49:58 am »

I shoot a lot of portraits, most of them at very wide apertures with basically no depth of field. I use the thumb button for autofocus, and generally use the center point and recompose. Yes, I do get a fair number of frames that are slightly off (and get tossed), but that's more to do with the razor-thin DOF and the subject moving around than any fault with the camera.

Try separating the AF from the shutter button. It'll take some time to get used to it, but in my experience in the long run it's better. Good luck.
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DarkPenguin

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Canon Focus-Point Selection and Portrait Framing
« Reply #6 on: July 03, 2010, 12:24:43 pm »

So buy a camera with more af points.
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walter.sk

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« Reply #7 on: July 03, 2010, 07:26:03 pm »

Quote from: DarkPenguin
So buy a camera with more af points.
I've been shooting with a 1DMkii, and they way I focus for portraits has spoiled me so that I don't want to use a camera that won't let me do it my way.

My camera has an oval that contains 45 focus points.  I use the center one for most of my pictures in landscape orientation.  The camera allowed me to register that center point for the default focus point.  I then set up the Star button to do AF while the button is pressed.  That means that after I focus and let go of that button, the AF is OFF, and will maintain the focus achieved while the button was down.  In all sorts of shooting, from nature to birds to city shots, separating the AF from the shutter button has been the greatest thing since sliced bread!

Now:  for portraits, my camera lets me choose another focus point and register it as well.  I have it set so that when I press another button (I don't remember what its symbol is and I don't have the camera handy) the single focus point switches to the rightmost focus point and turns on the AF, which it will hold as long as I have that button pushed (conveniently, with my thumb). This is great for a landscape shot where the subject is about 1/3 of the way in from the right.  But the real advantage comes when I rotate the camera for a portrait.  The focus point is now at the top of the camera, and in just the right spot for focusing on the eye in a portrait.  This even avoids the "focus & recompose" error, which at a wide aperture can be visibly off because of the (desirable, in most cases) shallow depth of field.

Yes, there are ways to "make do" with cameras that don't have this capability.  But when I bought this camera it was after I compared specs of many cameras, against a list of what I really considered necessary for my type of shooting.  The extra money I sank into the camera seemed like a hardship six years ago, but the many features of the camera that seem tailored to my way of shooting have made it worth it over and over again.

Another thing I would not be without is the ability to bracket exposure by up to +/-3 stops, and to shoot a bracket of 5 or 7 shots (for HDR).  I shudder to think of the expense when my camera gives up the ghost, but spending a few thousand dollars on a camera that won't do what I need it to would be a very bad decision.  In this case, I'm happier with the lower number of pixels and the smaller sensor than a full frame camera that would curtail the way I like to shoot.


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dwdallam

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Canon Focus-Point Selection and Portrait Framing
« Reply #8 on: July 03, 2010, 08:10:42 pm »

Quote from: k bennett
I shoot a lot of portraits, most of them at very wide apertures with basically no depth of field. I use the thumb button for autofocus, and generally use the center point and recompose. Yes, I do get a fair number of frames that are slightly off (and get tossed), but that's more to do with the razor-thin DOF and the subject moving around than any fault with the camera.

Try separating the AF from the shutter button. It'll take some time to get used to it, but in my experience in the long run it's better. Good luck.

How is that different as - a matter of focus - than using the half shutter button, recompose, shoot method? I'm wondering if I'm missing something.

One other thing I thought might be what the OP is having a problem with is using one of the nine available focus points is that I think you have to set in camera to ONLY use the selected focus point, or it will still try to average.
« Last Edit: July 03, 2010, 08:17:11 pm by dwdallam »
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DarkPenguin

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Canon Focus-Point Selection and Portrait Framing
« Reply #9 on: July 03, 2010, 08:50:59 pm »

Quote from: dwdallam
How is that different as - a matter of focus - than using the half shutter button, recompose, shoot method? I'm wondering if I'm missing something.

From a focus standpoint it should be the same.  But I believe that has exposure ramifications.

Quote
One other thing I thought might be what the OP is having a problem with  is using one of the nine available focus points is that I think you have  to set in camera to ONLY use the selected focus point, or it will still  try to average.

Unless the rules for AF Servo are different I'm pretty sure that selecting an AF point tells the camera to use that AF point and only that AF point.
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dwdallam

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Canon Focus-Point Selection and Portrait Framing
« Reply #10 on: July 04, 2010, 01:52:05 am »

Quote from: DarkPenguin
From a focus standpoint it should be the same.  But I believe that has exposure ramifications.



Unless the rules for AF Servo are different I'm pretty sure that selecting an AF point tells the camera to use that AF point and only that AF point.

Well then it's the same thing then, and yes, you have to NOT use the servo or it does focus every time you press the release.

I think the OP was wondering how he could get an auto-focus point in the part of the lens he wanted. I agree. Why not allow us to choose a focal point anywhere there are focus points? There just is no way to do that as of today. The closest you can come is to choose the point closest to what you want in focus, then recompose.
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DarkPenguin

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Canon Focus-Point Selection and Portrait Framing
« Reply #11 on: July 04, 2010, 02:34:40 am »

Or use a m43 camera and put the focus point wherever you want it to be.
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solardarkroom.com

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Canon Focus-Point Selection and Portrait Framing
« Reply #12 on: July 04, 2010, 02:19:30 pm »

Quote from: dwdallam
How is that different as - a matter of focus - than using the half shutter button, recompose, shoot method? I'm wondering if I'm missing something.

One other thing I thought might be what the OP is having a problem with is using one of the nine available focus points is that I think you have to set in camera to ONLY use the selected focus point, or it will still try to average.

In the last year or so I've been doing headshots/portraits with just one focus point selected which I select via the thumb dial in the moment after framing. What I experienced when allowing the camera to choose and average points was an unacceptable amount of shots focused on the tip of the nose for example and rendering the eyes too soft for my liking. I don't want to stop down much beyond f5.6 most of the time. I've not felt confident achieving focus and moving the frame since I imagine there will be too much movement between my subject and camera. I will have to properly evaluate that with some practice next time...just give it a shot despite my reservations.

My continued thanks for everyones thoughts on the matter.

David
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dwdallam

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Canon Focus-Point Selection and Portrait Framing
« Reply #13 on: July 04, 2010, 06:57:51 pm »

Quote from: solardarkroom.com
In the last year or so I've been doing headshots/portraits with just one focus point selected which I select via the thumb dial in the moment after framing. What I experienced when allowing the camera to choose and average points was an unacceptable amount of shots focused on the tip of the nose for example and rendering the eyes too soft for my liking. I don't want to stop down much beyond f5.6 most of the time. I've not felt confident achieving focus and moving the frame since I imagine there will be too much movement between my subject and camera. I will have to properly evaluate that with some practice next time...just give it a shot despite my reservations.

My continued thanks for everyones thoughts on the matter.

David


OK if that's the problem, then set the camera to ONLY use your selected auto-focus point. The only problem you should have when moving the camera to recompose is that of the focal plane of the lens compared to the new focal point.

Try this from a Luminous Landscape veteran:
http://www.visual-vacations.com/Photograph...mpose_sucks.htm
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MarkL

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Canon Focus-Point Selection and Portrait Framing
« Reply #14 on: July 06, 2010, 07:28:54 am »

Select the closest focus point and recompose when you take the shot (assuming you have teh camera set up with AF decoupled from the shutter release). The recompose will be so small with the cloest af point selected the change in plane of focus will be negligable is almost all circumstances.

The real issue is doing this with moving subjects where recompose is not such an easy option, then you have to hope the af tracking does a good job as you recompose.
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solardarkroom.com

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« Reply #15 on: July 06, 2010, 11:25:39 am »

Quote from: dwdallam
OK if that's the problem, then set the camera to ONLY use your selected auto-focus point. The only problem you should have when moving the camera to recompose is that of the focal plane of the lens compared to the new focal point.

Try this from a Luminous Landscape veteran:
http://www.visual-vacations.com/Photograph...mpose_sucks.htm

Thanks for the link. I like the idea of shooting portraits with a longer lens: I've been using the 24-105mm f4 and occasionally the 100mm f2.8 macro ("Can you smooth out my pores?"). Occasionally I've tried my 50mm f1.4 and 135mm f2.8 Carl Zeiss leftover from my CONTAX but my eyes do not serve me as well as they used to with manual focus. Now I think of it I should compare viewfinder brightness between the CONTAX and the 5DmkII. When I compared the 30D it was horrifying and I've assumed the 5D would be more comparable but I'm a little hesitant to (possibly) discover my latest digital monster still pales in comparison...

Again, I appreciate everyone's time and expertise!

David
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stever

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« Reply #16 on: July 06, 2010, 11:46:36 pm »

after focusing with your thumb for a (not very long) while, you'll wonder why any modern camera has half-press shutter release focusing (for the same reason as first curtain synch default?)

if you're regularly photographing moving subjects - particulary when you know in advance which way they're going - then moving the focus point can (i'd be interested in hearing of other uses), otherwise i'm extremely happy with center point focusing with my thumb and composing independently - or manually focusing in liveview.

i've never found any use for camera-selected autofocus and assume this is a feature that is easier to engineer and build than improving speed and accuracy of center point focusing and compensating for lens focus shift  - or improving camera and lens tolerances (or factory testing and coding micro-focusing values for bodies and lenses)

micro-focus adjustment is a band-aid that gets most of the performance out of high resolution cameras and existing lenses under most circumstances at the expense of the users time
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