What exactly do you focus on when shooting a subject?

[NedM]

I shoot a lot of portraiture and one of the many problems I face is achieving tack sharp focus on my subjects.

I shoot on manual mode, single point focusing (recompose) and switch on the auto focus on my lens.

When I'm shooting my subject, I always try to focus on the eyes.
Honestly, when looking through my viewfinder the subject looks sharp and I take the picture.
Then when I get home and look at that same photo zoomed in it looks soft and just slightly out of focus.

I don't get it?

This happens a lot to me, either the focusing is slightly behind or in front of my subject. (I usually use my 50mm 1.8 or 1.4)

I tried manual focusing but it yields the dsame results.
I look through my viewfinder, manually focus it, and when I blow the image on my computer screen it's soft.

What am I doing wrong?
What do I focus on when shooting my subjects?

Note I usually shoot in shade on sunny days or in direct sunlight. (Sun is behind subject)

 

[NedM]

The only solution I have found to combat this situation is to switch into live view mode on my 600D and magnify the image then manually focus until sharp.
It works wonders but it's a hassle going in and out of live view mode and recomposing is harder.

 

[Scatterbrained]

A few things to think about.
Don't focus and recompose. Use the appropriate AF point and put it right on the closest eye. If that means shooting a wee bit loose and cropping later so be it. It's good to leave a bit of room anyway for non native aspect ratios.
Remember that your AF points need adequate contrast to focus. If you can't see contrast under the AF point it's likely your camera can't either.
Remember that non cross type points are sensitive to contrast in one specific direction. It does no good to put horizontal contrast under a point that is sensitive to vertical contrast.
If you're using a fast prime, remember that the focusing screen in your camera can't show accurate DOF at apertures faster than f/2.8. Just because it looks "in focus" doesn't mean it is. Which is one more strike against focus/recompose.
Don't use AI Servo. Use One Shot. The instant you hear the confirmation, press the shutter.
Make sure you're standing and holding the camera correctly to maximize stability.
Make sure you're not trying to shoot at or near a lenses minimal focus distance, that's just asking for trouble.

I don't know how much, if any, of this applies to you, but I figured I rattle a few things off just in case.

 

[mmaria]

you got a fine advice here...

Here's my way, and it doesn't have to be your way.

I always focus and recompose. It's just my way of doing things and I simply can't see myself doing anything differently. Maybe I will one day, but until then, this is the way I'm comfortable with.
That being said, I always have dof and posing in mind when it comes to focusing on people's eyes. There are slight differences in how close are the eyes to the lens, where are you (your camera) standing in relation to them, what focal length... that you always need to keep in mind.

 

[NedM]

you got a fine advice here...

Here's my way, and it doesn't have to be your way.

I always focus and recompose. It's just my way of doing things and I simply can't see myself doing anything differently. Maybe I will one day, but until then, this is the way I'm comfortable with.
That being said, I always have dof and posing in mind when it comes to focusing on people's eyes. There are slight differences in how close are the eyes to the lens, where are you (your camera) standing in relation to them, what focal length... that you always need to keep in mind.

I never understood this concept.

What does dof, distance from my subject and the focal length have anything to do with achieving sharp focus?

Where can I learn more about this?
I know the wider the aperture the more shallow you dof will be but does this mean that the farther back I am away from my subject at a wide aperture the harder it is to achieve sharp focus?

 

[curtyoungblood]

DOF field relates to this because it describes how deep the area of the picture that appears in focus is. If you accidentally focus on the tip of a subject's nose at 1.4, the eyes will appear out of focus, but at f8 they will likely appear in focus.

 

[Braineack]

Show us an example of a photo you took where the focus isn't quite what you expected.

Focus really shouldn't be hard to achieve, but it would be hard for me to achieve while hand-holding the camera, in manual mode, with a live subject. I could imagine plenty of misses. Are you at least using your camera's focus notifier?

Distance shouldn't matter as well. This was taken at 200mm and f/3.2:

and the sharpness of that crop:


Zach - Cropped by The Braineack, on Flickr





Personally, I'm not a fan of focus and recompose, because if I'm shooting at a low f-stop, it could mean that when I recompose with teh DOF being so narrow, it could miss my intended focus. But what I noticed that's leading to, on my D600, are subjects that are oddly framed and I need to crop. This is due to the very small focus area in regards to the entire frame.

 

[paigew]

I back button focus, toggle and recompose. I will toggle if I can but if not I recompose with the closest point. I also shoot in al servo mode. And I shoot mostly wide open. I personally think al servo mode is the key

 

[tirediron]

What does dof, distance from my subject and the focal length have anything to do with achieving sharp focus?

Where can I learn more about this?
I know the wider the aperture the more shallow you dof will be but does this mean that the farther back I am away from my subject at a wide aperture the harder it is to achieve sharp focus?

Just everything. The larger the aperture, the longer the focal length of the lens, and/or the less the camera-to-subject the shallower the the depth of field, and the greater the need to be spot-on with your focus. If your DoF is from 10' to infinity and your subject is at 40', you don't so much have to worry about nailing that near eye, whereas if your DoF is only 12" and the subject is 20' away, you have almost zero margin for error. Read this tutorial here, and study this calculator here to learn more.

 

[runnah]

I never focus and recompose personally. Might have to do with the 61 focus points my camera has or maybe i just suck at it. We may never really know.

I always focus on the eye(s).

 

[paigew]

I never focus and recompose personally. Might have to do with the 61 focus points my camera has or maybe i just suck at it. We may never really know.

I always focus on the eye(s).

I don't have all my points active.

 

[runnah]

I never focus and recompose personally. Might have to do with the 61 focus points my camera has or maybe i just suck at it. We may never really know.

I always focus on the eye(s).

I don't have all my points active.

Well shame on you!

 

[SDreams]

You mentioned that youre usually outdoors. Do you use a tripod or remote shudder release? Maybe these as well as turning off your lens' VS control would help as well.

 

[paigew]

I never focus and recompose personally. Might have to do with the 61 focus points my camera has or maybe i just suck at it. We may never really know.

I always focus on the eye(s).

I don't have all my points active.

Well shame on you!

faster than scrolling through them all. My subjects are very fast and random with their direction of movement LOL. Toggle to the closest, then recompose.

Plus some points aren't as reliable.

 

[runnah]

I don't have all my points active.

Well shame on you!

faster than scrolling through them all. My subjects are very fast and random with their direction of movement LOL. Plus some points aren't as reliable.

Do you use the joystick?