[JimJohnson]

What not to do...

I tend to use center focus and recompose (slightly and well within depth of field). If you do this you have to hold the camera in the half-press position (assuming you don't use the AF back button) until you achieve 'the moment'. It worked fine with the K-30. It doesn't work as well with my K-3. The half-press point is finer on the K-3 and if you do let go, you have to re-center on the subject, half-press, recompose and wait. Here is where it got frustrating. The camera has supposedly re-focused, but in reality you are essentially at the same focus point as before. Certainly my 18-135 hasn't budged. And when you fully press the shutter - nothing. I suspect the lens hasn't moved enough that the camera believes you have re-focused and if in focus priority release - there is no release.And you just missed 'the moment'.

So I either have to give up recomposing (hard to do as I don't trust the camera to pick the right subject, nor do I want to fiddle around selecting a focus point). Use the back AF button (will probably teach myself to do that rather than the shutter release), or what I have done - turned off focus priority shutter release. I KNOW the subject is still in focus because neither it nor I have moved.

[clackers]

What not to do...

I tend to use center focus and recompose (slightly and well within depth of field). If you do this you have to hold the camera in the half-press position (assuming you don't use the AF back button) until you achieve 'the moment'. It worked fine with the K-30. It doesn't work as well with my K-3. The half-press point is finer on the K-3 and if you do let go, you have to re-center on the subject, half-press, recompose and wait. Here is where it got frustrating. The camera has supposedly re-focused, but in reality you are essentially at the same focus point as before. Certainly my 18-135 hasn't budged. And when you fully press the shutter - nothing. I suspect the lens hasn't moved enough that the camera believes you have re-focused and if in focus priority release - there is no release.And you just missed 'the moment'.

So I either have to give up recomposing (hard to do as I don't trust the camera to pick the right subject, nor do I want to fiddle around selecting a focus point). Use the back AF button (will probably teach myself to do that rather than the shutter release), or what I have done - turned off focus priority shutter release. I KNOW the subject is still in focus because neither it nor I have moved.

Yep, back button separates the functions and means you don't need to do index finger gymnastics.

[Nicolas06]

What not to do...

I tend to use center focus and recompose (slightly and well within depth of field). If you do this you have to hold the camera in the half-press position (assuming you don't use the AF back button) until you achieve 'the moment'. It worked fine with the K-30. It doesn't work as well with my K-3. The half-press point is finer on the K-3 and if you do let go, you have to re-center on the subject, half-press, recompose and wait. Here is where it got frustrating. The camera has supposedly re-focused, but in reality you are essentially at the same focus point as before. Certainly my 18-135 hasn't budged. And when you fully press the shutter - nothing. I suspect the lens hasn't moved enough that the camera believes you have re-focused and if in focus priority release - there is no release.And you just missed 'the moment'.

So I either have to give up recomposing (hard to do as I don't trust the camera to pick the right subject, nor do I want to fiddle around selecting a focus point). Use the back AF button (will probably teach myself to do that rather than the shutter release), or what I have done - turned off focus priority shutter release. I KNOW the subject is still in focus because neither it nor I have moved.

I use the back AF button set to AFC by default, I got the habit very fast honestly (1 day?) and I use off center points.

So if I need to shoot a portrait with the focus on the eye and tiny dof, I just select the AF point I need, ask the AF to do its job so there no need to recompose. I agree that the ergonomics to select that AF point are not as good as I would like, true . I hate in particular that you can eather select the focus point or select JPEG mode, burst modes, white balance etc with the same buttons.