fine tuning focus

[momx4]

I got a 50mm 1.4 lens for my Canon Rebel about 9 months ago. I love the lens, but am having trouble getting faces to not be blurry. I typically photograph my kids outside mid morning or evening. I usually have the ISO set at 100-400 and my aperture set at 3.2-6. I also have my focus point set in the center or the far left. I don't like it being in the center but someone told me it gets the best focus on the center point. I focus on the eye and lock the focus then shoot. Can anyone tell me what I am doing wrong?

the first one I shot with my kit lens and love the picture. this is what I am looking for in sharpness.

the 2nd and 3rd one is an example of the blur I am referring too.

the last one I don't know why I couldn't get them all in focus. I had the f/stop up to 10.

Thanks for any suggestions!
Dru

[Hill Country Hack]

Cute crowd of kids you have there.

Let me preface by saying I am by no means a professional, I'm consider myself a mediocre hobbyist so take what I say with a grain of salt.

Here are 2 cents worth.

I am perplexed on #3, all is in focus (arms shirt at teh collar out to the sleeves)except for the face so I can't imagine it is a DOF issue and therefore leads me to think camera shake?

#2 it appears the top front of the dress is in focus and then it falls off a bit.

What I can come up with is...camera shake, focal point changing by either the kids or the camera moving back or forward (if shooting wide open).

I only use the center AF point. When I'm taking any type of shot (except landscape/cityscape, then I go for the hyperfocus point) I center my subject and shoot with a large enough framing to adjust the composition in PP. I really don't do group shots except for snapshots so I can't help you there.

I know I'm not being much help, but maybe a couple of things to rule out.

[zona5101]

#2 looks like motion/camera shake. What was the shutter speed?
#3 looks like you lost the focus...inadvertently let your finger off the focus hold and it grabbed something else
#4 looks like the focus is on the bench... it's pretty easy to accidently change the focus selector square so perhaps you didn't notice it wasn't on the kids eye....
DOF is a function of lens focal length and subject to lens distance in addition to the actual fstop...so f10 doesn't guarantee you infinite focus. For example at f10, 50mm lens and a subject to lens distance of 4 feet your resulting dept of field is under a foot. Now 12" you would think would be enough but i bet there is more than a foot between the bench slat and their noses...

[Tzetsin]

I find canons multiple focus points a real pain in the butt. Try setting your camera to only use the center point then lock and losely compose with the subject's eyes on the focus point. If this solves the problem then the issue is narrow DOF with the AI autofocus choosing something other than the eyeball.

I also want to note that your white balance is off on all but the first image. Take it out of manual and put it on shade when taking shots of the kids outside. Even if its sunny out, shade will give a nice warm tint to the portraits that will make their skin tones glow really nice. Shoot in raw mode as well, so you can adjust it any way you like after the fact as well.

[inkista]

#2 definitely a misfocus.

#3, my guess is your subject is inside the minimum focus distance of the lens (1.5'), or an outer AF point was used. If you open up the photo in Canon's PhotoBrowser, you can get the display to highlight the actual AF point that was used. It may not be the one you thought you were using.

Secondly, did you wait for autofocus confirmation? (i.e., for the AF point to light up and, if set, the camera beeps). And if you did use center-point and recompose, did you then change your angle or subject distance? The thinner DoF can still be thrown off if you did either.

#4, I agree there's some motion blur there, but it also looks like misfocus to me.

This is just me but, I would check:

1) That only the central AF point is active, not the entire grid. With a dRebel, the center AF point is your own f/2.8 cross-type sensor. It's better for wider lenses; it uses distance information in both vertical and horizontal directions to affect autofocus, so it's more accurate the most of the other points.

2) That the camera's using One Shot AF mode.

3) That when you aim the central spot on the eyes, and half-press that you then get AF confirmation (the AF point lighting up red); and that you did not release the shutter from half-press before you pushed to take the picture. If your finger came out of half-press, you've effectively reset the focus.

4). When you recompose, take care not to change your position/distance to the subject, and that whatever angle shift you're doing is still within your DoF.

[cyber3d]

All the responses are on the nose. I would add that you practice focus points/planes on a still life. And try hand held compared to tripod shots.