Out of Focus

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Mar 26, 2007
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How come sometimes when I take a pic the persons face is out of focus. I know silly question but it bothers me! I will post an example. Is it my lens or me!!

n628210132_319872_4399.jpg
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Thanks
Sarah:Confused:
 
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Sarah,

This particular shot looks like you may have used too slow of a shutter speed to "freeze" the action, and thus it looks soft. In other cases, the camera may choose to focus on another area and the shooter doesn't realize this and change the AF sensor selection.

Sean
 
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It's hard to say much about your problem, Sarah. The example doesn't look too bad to me, but it's a little underexposed, which makes it difficult to see the point of focus on this subject. It would be helpful to know your camera settings from the EXIF. :smile:
 
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Exif

It's hard to say much about your problem, Sarah. The example doesn't look too bad to me, but it's a little underexposed, which makes it difficult to see the point of focus on this subject. It would be helpful to know your camera settings from the EXIF. :smile:

Here is the exif 1/60 shutter f4.5 flash fired:auto, return light detected.
Now what does return light detected mean? Is there something wrong with my lens?

Sarah
 
Another possible reason for an out-of-focus or slightly fuzzy shot is if the photographer was too close to the subject and not at the comfortable focusing distance for the lens.

If you were using flash, you could have used a different aperture in order to ensure more sharpness, too; f/4.5 is not giving you a lot of latitude here.
 
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Here is the exif 1/60 shutter f4.5 flash fired:auto, return light detected.
Now what does return light detected mean? Is there something wrong with my lens?

Sarah

IIRC, return light detected means that the flash was used in either iTTL or TTL-BL fill flash, and the camera recognized that and set the exposure accordingly. It doesn't have anything to do with the lens.:smile:

Your shutter speed is okay for flash, assuming you have fairly good hand held technique. At f/4.5, I'm guessing that you were at the long end of the 18-70, which means it's wide open, giving you more shallow depth of field.

My guess is that you have a couple of minor issues here. The scene is too dark for reliable, accurate autofocus on a moving subject. Slight movments by you or the subject when DOF is shallow, can significantly change the point of focus. You can compensate, as mentioned, by stopping down a little more, to f/5.6 or so. It wouldn't hurt to use either a higher ISO or a higher EV flash value, or both, to avoid the slight underexposure.
 
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I beg to differ with the majority here, I don't think you have an underexposure here (I havent looked a the histograms, but it looks alright to me).
Also, with a Flash, you won't notice subject movement unless you go way slower and even then, the bluriness will overlap with the sharp part. The flash freezes the image, so even moving objects at slow shutter speeds will be frozen.

I'm willing to bet you had one of three problems:
1) Not enough light to focus correctly
2) You were too close to the subject (so the lens couldn't focus)
3) Your system has a backfocusing problem.

(1) is unlikely because the D70 does have a helper light which is pretty useful in low light.
If you see this problem often, then I'd try to test the camera for backfocusing with that lens. There's a little PDF going around that helps you determine the focus accuracy.
 
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Another possibility

This may be off-the-wall, but you might check to see what your in-camera sharpening is.

The posted image resolution is too low to tell for sure, but it almost looks like an image with camera sharpening turned off. When I do levels/curves in Photoshop to "fix" the underexposure, then use Smart Sharpen at 40% and .6 pixels, I get this (yes, I know, the sharpening artifacts show):

oof_boy.jpg
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Joined
Mar 26, 2007
Messages
520
Location
Ontario,Canada
How do I find This!

I beg to differ with the majority here, I don't think you have an underexposure here (I havent looked a the histograms, but it looks alright to me).
Also, with a Flash, you won't notice subject movement unless you go way slower and even then, the bluriness will overlap with the sharp part. The flash freezes the image, so even moving objects at slow shutter speeds will be frozen.

I'm willing to bet you had one of three problems:
1) Not enough light to focus correctly
2) You were too close to the subject (so the lens couldn't focus)
3) Your system has a backfocusing problem.

(1) is unlikely because the D70 does have a helper light which is pretty useful in low light.
If you see this problem often, then I'd try to test the camera for backfocusing with that lens. There's a little PDF going around that helps you determine the focus accuracy.

Thanks for the possiblilities I was wondering if you could tell me how to find the PDF that tells me how to do this!
 

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