Multi or single point focus?

What do you use/prefer?

My first impressions of my DS2's focussing is that it's somewhat slow. The multi-point focussing seems to hesitate before it decides.

Intuatively, I think single point might suit me better. What do you use most?

John

I only ever use the centre-spot for focussing. I can see little point in multi-point focus where the camera decides which focus point it is going to use. It can't possibly know which point in the image I want to focus on and can sometimes ruin an otherwise perfectly good image.

I am a firm supporter of modern cameras 'intelligent' electronics . . . as long as it can be turned off. My preference then is for centre-spot focus, average or centre-weighted metering, and either fully manual or aperture priority for exposure. Oh, and RAW mode, so that I have some latitude for exposure errors (mine, not the cameras).

Centre-spot focusing always. I tried letting the camera decide for about 5 seconds before making the switch! It can't know what I'm wanting to focus on, so I decide by focusing, locking the point with a slight depress of the shutter release and then re-composing as desired before taking the picture.

I curse the choice of focus points, because sometimes you can inadvertently switch to auto.

G

Depends on the photograph, but I use multi-focus points more, especially in low light. However, I've got the setting to switch to single at a touch of a button.

Personally I always use centre focus only. But you have to train yourself to use it well... and I turn off the "focus-on-half-press".

That way, especially in low light, I:
* point the very centre of the viewfinder at something with contrast (eye balls for portraits)
* press the "AF" button (*ist-D) or "OK" button (*ist-DS) to focus
* reframe, and press the shutton

Can't live without it now and even though the *ist-DS is slower at focussing than the *ist-D (the motor seems to have less torque), even the *ist-DS with that method kept up and let me accurately focus in low light with a 50mm/f1.4 lens shooting at f2

My wife, on the other hand, prefers to have focus-on-half-press and multi point focus because she couldn't get on with the above method.

Matt

I tend to use manual selection of focus point. That way you can track subject movement without having to recompose.

There is also some doubt that focus-recompose works when close to the subject using a wide aperture:

http://www.outbackphoto.com/workshop/phototechnique/essay06/essay.html

Cheers,
Reuben0

A valid point Reuben0, and one that I'm aware of.
However, in practise, though, I've rarely had an issue. Probably just the type of shot I take, and where the recomposition requires only a reframe (thus minimising the error).
Matt

As you say Matt, it depends on the kind of pictures you take. Unless you're fairly close to the subject it doesn't make much difference.

I tend to like portraits with very narrow DOF and I certainly experienced this problem until I read the above article and the penny dropped (finally!).

Cheers,
reuben0

Thanks for the link Reuben0, very interesting artical, maybe this is the cause of all the back focus issues people complain about using fast Sigma lenses.

I would say that the article is spot on and this is why I always try to keep the camera perpendicular to the subject. Of course it isn't always possible because of the subject distance but then the effect is less pronounced anyway as the distance increases.

I definately prefer to use the center-focus point and find that for general purpose shots, the multi-pattern metering is pretty flawless.
Center-weighted and spot metering may be perfect in experienced hands but you really do need to be aware of it's limitations.

Multi-point autofocus is one of those things that the engineers do just because they can. It's useless for normal use, the camera has no idiea what you want to focus on!

I use the center focus point most of the time, or I select a specific sensor for portraits when I know the eyes will be at one end of the frame.

Hi Reuben0

As this a great bit of info I took the liberty to post the link across at the Pentax forum on DP review, hope you don't mind.

There are plenty of times I ditch AF altogether and use manual focus. Sometimes for portraits and almost always for macro.

I'm a bit like that too John, I seem to be using manual focus more and more now, since I gave away my FA100 Macro and paid an extortionate amount for an SMC-A 100 f2.8 my body seem to be set on MF most times now.