Focusing trouble.

[justkatie02]

EXIF DATA::
Nikon D7000
50mm f/1.4 lens
Manual Mode

ISO 200
1/4000
f/1.4

Single Point AF on subject's face
Matrix Metering
Flash did not fire

This shot was taken is succession with 10 other frames... half were like this - and half were sharp. Settings were not changed...

Ok - so this is a very common problem I'm having. Single point focusing set on subject's face - yet 2' behind her is where it is sharp. This is happening A LOT. Very consistently. I have no idea how to correct this problem.

I've troubleshooted this issue in the following ways in various combinations over a period of 10 shoots (3 months) and still I'm getting the same results...

Switched from matrix to spot metering, switched from single point to automatic focusing (39 point dynamic), switched from Manual to A to S... all with similar results. Even locked my single point AF in the center of my viewfinder, depressed shutter half way to lock focus - recomposed and fired away...

I'd say out of a series of 10 frames... all with the focus point on the subjects face - 5 will be sharp - and 5 will do a variation of above.

I can't figure it out - why is my camera focusing willy nilly???
Thank you for checking this out!

[MrJones]

it's hard to say if it's a problem with your technique or a camera issue.
are you focusing and releasing your finger from the shutter button before actually taking the photo?

[Matthew_Scullion]

Wild guess here but is your camera is AF-S or AF-C? If in AF-C, which is designed primarily for moving targets, the camera will refocus when as you move it one whatever your single af area is pointed at.

Another thing, using your camera LCD (rather than a computer) view the photo then use the arrow pad to scroll through the review options. One of those will show you which AF area was in use as the photo was taken.

If you wish please post the full Nikon EXIF data for more info.

Hope this helps.

[justkatie02]

no... not taking my finger off the shutter... i have my camera also set to Continuous Low... i'm a click click click person... take waaaay more than I should for a given scene - a lot of that has to do with this issue - if 5 out of every 10 are out of focus - i don't have much confidence that I'll get the shot unless i take a bunch of frames.

oh yeah - and i've also double checked that both my camera and lens are set to "auto focusing"

i'm stumped.

[justkatie02]

Matthew - well - I currently have it set to AF-A... bad choice?

Here is the entire EXIF data...

Camera Nikon D7000
Exposure 1/4000 sec
Aperture f/1.4
Focal Length 50 mm
ISO Speed 200
Exposure Bias 0 EV
Flash Off, Did not fire
X-Resolution 72 dpi
Y-Resolution 72 dpi
Software Adobe Photoshop Lightroom 3.4.1
Date and Time (Modified) 2011:06:01 14:31:25
Artist Katie Pegher
Copyright Copyright 2011 Katie Pegher Photography
Exposure Program Manual
Date and Time (Original) 2011:05:31 06:44:01
Date and Time (Digitized) 2011:05:31 06:44:01
Max Aperture Value 1.4
Subject Distance 4294967295 m
Metering Mode Multi-segment
Light Source Unknown
Sub Sec Time Original 70
Sub Sec Time Digitized 70
Sensing Method One-chip color area
CFAPattern [Red,Green][Green,Blue]
Custom Rendered Normal
Exposure Mode Manual
White Balance Auto
Digital Zoom Ratio 1
Focal Length In35mm Format 75 mm
Scene Capture Type Standard
Gain Control None
Contrast Normal
Saturation Normal
Sharpness Normal
Subject Distance Range Unknown
Compression JPEG (old-style)
Copyright Flag True
URL www.katiepegher.com
Coded Character Set UTF
Lens 50.0 mm f/1.4
Lens ID 160
Image Number 11351
Approximate Focus Distance 4294967295
Color Transform YCbCr

[inkista]

Originally Posted by justkatie02

Matthew - well - I currently have it set to AF-A... bad choice?...

Probably. With AF-A you really have no control: the camera's trying to decide whether it should be in AF-S or AF-C. Likely something in the frame moved, the camera assumed you wanted a tracking-focus shot and switched to AF-C and then focused on what was moving (say, tree branches in the wind).

For a non-travelling subject, use AF-S.

[Matthew_Scullion]

Hi Katie,

Can't guarantee that's the probem but I would certainly suggest it might be. Try the following steps:

Set camera to AF-S mode. Set AF-Area to single area. Select the area that you want to use using the arrow keys on the back of the camera (it should lite up in the viewfinder the one you've chosen, and also show it diagramatically on the mini LCD).

Then use the half-depress shutter technique to focus on your subject, re-frame then take your shot. That should work.

One other trick you could try (good for bursts of shots I find) is focus using the technique above on your chosen subject but release shutter before you take the shot. Switch to manual focus mode using the switch on the body, then snap away... no re-focussing so no chance of going out of focus.

A posher way of doing the above is to use the option to re-program the button on the back of your camera to be the focus lock. I have a D200 which has a dedicated button for this but on the D7000 I think you have to change a menu option to make the AE-L/AF-L button do it.

You mentioned matrix vs spot metering in your initial post. As far as I know, this should make no difference at all to the focus points.

Hope some of this helps.

Regards,

Matthew

[justkatie02]

hey guys - thanks for the great feedback...

it would make sense that my camera would be confused by something in the background that might be moving (rustling leaves, waves) if i have the focusing set to AF-A...

but what about this example (attached) - another shot where clearly - I'm having the same problem - but it's indoors.... no background movement.

i had my focus point again on her face in this one - fired about 5 or 6 frames off without taking my camera away - a few were in focus - and a few were like this - where the draperies in the hotel room are sharp... and i didn't change a thing in between rounds... so a 50-50% on good/bad shots

hate to beat a dead horse about this - but this has been such an ongoing issue for me in multiple shooting environments that I'm desperate for answers!!!

i would prefer this were a technical error on my part v. a camera issue - sending it in for repair makes me sad... hate being without it....

my only fear - is that when i used my D90 - this problem was much more infrequent.
thanks again for your expertise out there!!!

[Wolfsburg]

Why dont you try renting or borrowing a different lens and see if that fixes your problem. If it doesn't then you know your camera needs repair, if it solves your problem then you know its the lens. Try to narrow this thing down.

[justkatie02]

thanks for the response... but i've tried it with a 50mm 1.4, an 85mm 1.4 and a 24-70 2.8...
same thing...

i've opened a help ticket with nikon and they've asked for sample images... however uploading them via their website has been an absolute pain in the but.

every time i get them uploaded and ready to submit - i either get "timed out" and kicked out - or the shots go through but nikon sends me an email that they don't have the full metadata and i should start over.

what a bunch of runaround.
sheesh.