AF point selection

[Snurk71]

Any experts want to offer their $.02 on AF point selection - using the center point (with recomposing if needed) vs. all focus points?

Thanks

 

[0bli0]

i am not an expert, but i use single AF spot that is approrpiate to the scene i'm shooting. it is very quick and easy to change with the af select button which is easily found with my thumb without looking (in both portrait and landscape orientation). on my body, you can limit the number of AF points through the selection process to make it quicker to change, if desired.

 

[ukcatfan]

I personally like to use all of my focus points unless I am in some situation where I am having a tough time getting the correct focus point. I have had my K100D for about eleven months now and I can count those times on one hand. Mine has eleven points and I believe that nine are cross type. I guess it would not make as much of a difference on a model with only a few AF points.

As for exposure, I go to center spot metering about a third of the time with center weighted averaging the rest of the time. I never use evaluative/matrix metering. Also, I typically lock the exposure before I lock the focus

Kevin

 

[JR6ooo4]

I use center point exclusively for live theater shots. The problem is by the time I lock focus and then move to compose the shot the subject actor often has moved out of the focus range. (stupid choreographers teling them to move around and stuff...)

same when I shoot soccer games. I can't risk missing the goal shot because the computer liked the contrast of one player over the other who might be farther away but is actualy the one who is shooting the goal. And the game is so fast that I shoot a little wide and plan on cropping to frame it well later.

Mikeeee

 

[handicap18]

My camera has 5 AF points. I use all of them and switch as needed. I think I use the top middle the most. Helps when you take a picture of someone to use that point to focus on their eyes and you don't have to recompose like you would when using the center point. Plus my focus lock button isn't in the most convenient spot and makes it harder to use. I do use it, but find it easier/faster to switch auto focus points. That control is better located and much easier found with my thumb.

 

[boBQuincy]

I use the center point as my default, and switch to other focus points as needed, such as when using a tripod and the main subject is not in the center.

 

[jann1033]

i like to use the center but for some reason my points keep changing which drives me nuts....( and i keep forgetting to look up what i have to do to stop that ) i find just the center is easier for me if i am trying to shoot something like a bug that moves, i know right where to put the square

 

[MarkBarbieri]

More often than not, I leave them all on and let the camera sort it out. That works particularly well if I'm focusing on something moving because it tracks better.

When I'm afraid that the camera cannot pick out what I want to focus on or if I'm using a very wide aperture, I pick a focus point and use that. As 0bli0 said, it's really easy to pick the focus point you want.

I often pick a focus point about a 1/3 of the way across the frame as I find that's most often where my subject is (or a 1/3 of the way down for portrait orientation shots).

When shooting through stuff (screen, fence, brush), I often leave the focus button alone and just go manual. The same is true when I'm shooting extreme close-ups because of DOF issues.

 

[SharonLowe]

My camera has 45 AF focus points and I prefer to keep them all on most of the time. I don't suggest using the center point other than in very limited cases because it doesn't facilitate following the rule of thirds, which greatly enhances images. If you do use the center point, then locking the focus and recomposing so your subject follows the rule of thirds would be a good idea.

 

[handicap18]

I'm amending my answer slightly. I did a little research to try and get my facts together and also to maybe help some people who might have no clue as to what we're talking about.

As you look through the view finder of my camera (Nikon D50) you see 5 rectangles, these are the AF points. Camera's vary from model to model (ie: Nikon D80 has 11, Canon 30D has 9, the new Nikon D300 has 15 and so on). From these points you can get upwards of 51 point AF area (on the D300) depending on which AF Area Mode you chose.

If you choose to use Auto Area or Closest Subject Area for example, the camera will choose which of the 5, 9, 11 or 15 areas have the main subject in them and focus there. Most times it includes more than 1 area (usually 2), thus giving 45 point or 51 point AF. This one I don't like. I think you'll find more images with out of focus subjects. Just my opinion though. On my camera this is the only AF option in AUTO or any of the preprogramed icon modes.

There is also Dynamic Area (Nikon) or Servo (I believe this is the term Canon uses) where you choose 1 of the focus areas, get a locked focus then as the subject moves the focus point will track and move to the appropriate focus area. You can initially choose the point you first want to focus on.

Then we have Single Area. This is the one I use. You choose which area you want to focus. If the subject moves you have to refocus. Really not a big deal as you just 1/2 press the shutter again. As I said in my other post I mostly find myself using the top middle or center point most of the time (both with the camera in horizontal or verticle position). I don't use the bottom middle very often. Looking back at the first few hundred pictures I took many of them are slightly out of focus or at least the subject I wanted was out of focus, but another section was in focus. My camera defaults to Closest Subject AF area. I get much better results now that I use single area and select the area that I want, not what the camera thinks is the right area.

Everyone has their own preferences. I've found it no big deal to change the AF points with the selector on the back of the camera. Its a bit akward to move my thumb up an inch or so to press the AF lock button.

This subject has come up quite a bit recently between some other friends and a few family members of mine. Using the center point and locking the focus by 1/2 pressing the shutter, then recomposing slightly seems to be the most used by other people I know.

I hope I didn't confuse anyone. I know most of us here already know this, but I wasn't completely sure on some of the termonolgy. I find if I research it, then type/write it out it helps me remember it more. So thanks for reading, even if you already knew this stuff.