Focus and recompose, myth or fact with digital?

[alessia_c.]

Lately I've come across some articles where some are saying that focusing and

recomposing should NOT be done with DSLRs.

 

Is there any truth any of this, looking back at some of my portrait pictures at

100%, I do notice that some images are actually soft.

Or is it maybe that they're all going to be slightly soft at 100% and aren't

supposed to be tack sharp?

 

Help...

 

Thank you

[michael_darnton1]

Focus-and-compose works equally as well with digital as it ever did with film, but now that you can move the sensor around rather than the camera, the technical advantage of that is obvious, and I use it, and get better results that way, when it's appropriate.

 

On less critical and changing stuff, though, where the focus spot isn't in the same place in every picture, I still focus-and-compose. The one thing I don't like is letting the camera pick the focus point, since it never seems to be as discriminatory in that as I am, and can't even equal focus-and-compose results.

[Matt Laur]

I do it all the time. It's more of a problem at close range, or with certain focal lengths, where swinging the camera back to the composition you want significantly changes the distance between the focal plane in the camera, the focused-upon in the shot. You really notice that when shooting very fast lenses that are - when wide open - producing a razor thing depth of field. But this has nothing to do with digital vs. film.

[digitmstr]

It all depends how far off axis the recomposed shot is from the focused position.

 

Normally, it doesn't cause problems. For example, if I focus on a model's eyes and then, re-compose a bit (WITHOUT changing the zoom and/or distance of course) everything is fine. However, if I am doing a series of shots, all in portrait orientation, I would normally use a focus point that is more in the appropriate zone as opposed to the center of the frame.

[phil_dawson2]

I used to do this, however I now use the arrow buttons on the back of my body, and after a few weeks it's quite quick to flick betweeen focus points.

[Ed_Ingold]

This technique is standard for digital or film when you are shooting hand-held. The cosine error is negligible in most cases, but could affect either medium equally.

 

When using a tripod (e.g., portraits and studio work), it's best to focus manually using the ground glass - it just takes a little practice. The image is NEVER sharp, so you focus past the sharpest point then backup up. Furthermore, you are free to engage you subject instead of fiddling with the camera.

[alessia_c.]

Hi guys, thanks for the replies, I really appreciate the help

 

Edward, I don't understand what you mean by focusing past the sharpest point and then backing up. I mean, I understand it in the sense of what you're saying on how to do it, but I don't understand the why. Hope that made sense. lol

[stephen_allan]

I think what Edward means, is that it is not possible to tell whether you have reached the point of sharpest focus on the focussing screen, until you go beyond it, and can then back up to the point of sharpest focus.

 

In other words. As you approach focus, the image will be getting clearer, and sharper as you get closer. But. If you stop focussing because you think it is the sharpest image, you may still be short of sharpest focus, and it is only when the subject starts getting fuzzy that you know you have achieved, and passed the point of best focus, and can back up to it.

[ricardo_tomasi]

<strong>Phil</strong>, could you give us some more info on those buttons in your body? Are they Pentax implants?

[b_jordan_munsayac]

In regards to autofocus, I've found that selecting and using the correct focal zone (my D40 only has 3) helps me compose my shots alot easier - I'm finding this helps keep re-composing down to a minimum. At times I'll use the focus lock button on my camera which helps in some situations too. When I first started using my camera I was letting the camera choose the focal zone, which at times was too smart for its own good, and never seemed to wanted to focus when I wanted it to. By manually selecting the focal zones, it gave me much more control in composing my images. When using my 50mm f/1.8, which has no AF on my camera, the focus indicator light on my D40 became my friend- I find I use the focus lock feature much more frequently on my manual lens, and the focus zone selection religiously on both AF and Manual lenses.

[Ed_Ingold]

Stephen nailed it! I would add just one thing. With practice, you learn to recognize how far you turn the ring past the point of best focus, then back up that distance by feel.