Pin Point Focal Points.

[Allan_Love_Jr]

Hi everyone.
I decided to change my Focal points on my Canon Digital Rebel XTi Camera today.
I did this one reason. Only to have the Camera focus on one spot. The "Center".
Especially when I Photograph Trains. When I use the other focal
points. The Camera has a tendency to focus on other things that I do
not want it to. Like when I stand on the UP Blair Hill. The focal
points focus on the ground and not further down the Track. Which in
turn causes the farthest point to be out of focus and the ground near
me becomes clear in focus. I mean I really like my camera alot and
would not give it up for anything else. Please what are your thoughts
on this topic? Am I right or am I totally wrong. Please let me know.
Thanks.

Allan Love Jr
Blair,Nebraska.

[krb]

Originally Posted by BNSFrailfan

Please what are your thoughts
on this topic? Am I right or am I totally wrong. Please let me know.
Thanks.

That is a very good idea that is very commonly recomended around here for the reasons you describe. Not sure what camera you are using but on the 40D and others you can configure the camera to use the joystick thing to select which AF point you want it to use, which is much faster than the other methods available.

[Allan_Love_Jr]

Originally Posted by krb

That is a very good idea that is very commonly recomended around here for the reasons you describe. Not sure what camera you are using but on the 40D and others you can configure the camera to use the joystick thing to select which AF point you want it to use, which is much faster than the other methods available.

And that is what I did too. I have the focal point set in the center now.

[fatphotographer]

When you say "change it to the centre" what were you using before? Another single point, or multipoint? Multipoint is set to pick up on the area with the most contrast and / or nearest. The hardcore rocks that are around the track are a prime target for the focusing if multipoint is used.

[Allan_Love_Jr]

Originally Posted by fatphotographer

When you say "change it to the centre" what were you using before? Another single point, or multipoint? Multipoint is set to pick up on the area with the most contrast and / or nearest. The hardcore rocks that are around the track are a prime target for the focusing if multipoint is used.

I was using the Multipoints.

[gjl711]

I think you'll find many here that often use the center focus point alone, myself included. It's the quickest way to insure that the camera has chosen the same object as you to focus on.

[dave kadolph]

There's more than one?

[Shutterbug Doug]

Sounds good. You can focus and recompose easier that way too.
I have found using all focus points is a hit or miss proposition with getting what you want if focus, in focus. Usually they will lock on the subject with the most contrast and closer to the camera, from my understanding. The center focus point is a cross type point, which means it focuses on the horizontal and vertical plane making it more reliable.

[walternewton]

You are right - YOU want to be deciding where the focus point is, rather than letting the camera do it. Modern cameras have lots of automation built in, the more experience you gain the more you'll find you want to turn that stuff off and take control yourself.

[Allan_Love_Jr]

Bingo. That is what I was looking for. Thank you everyone.

[Chet]

Originally Posted by BNSFrailfan

Bingo. That is what I was looking for. Thank you everyone.

Bingo? I thought you were looking for focal point help? You probably want to get on some church forums if you're looking for bingo.

[Beaufort 12]

Originally Posted by FuryMe

Bingo? I thought you were looking for focal point help? You probably want to get on some church forums if you're looking for bingo.

Probably related to his old focus method with multi-point.

Focus, and pray ...

(Where is here the smiley button?

Ah, here it is

[fatphotographer]

Multipoint was probably the problem. If you decide on your composition first, then choose the focus point that covers the most important part of the picture, then shoot, you should get much better results if you are shooting moving subjects in servo.

If you are shooting stationary subjects, you can put the camera in single shot focusing, then zoom and compose your shot, put the centre focus point over the point you want in focus, push the button half way down to get the focus and keep your finger there to lock it whilst you recompose the shot, continue pressing the button to take the shot.

Those techniques might help, rather than relying on the camera.

[charlesking]

Focus-and-recompose (using the centre point because it's always the best) is an absolute staple of good photography. Automated focus selection never works well, that's why manufacturers have spent so much on working out face-detection algorithms.

The one thing for which you need to watch out is that some lenses have a slightly curved focal plane, meaning that if you focus on something at the centre of the lens's field then rotate the camera so it's near the edge, the focus on that subject may shift slightly. If you have a static subject, it's always worth taking several shots, and even bracket the focus slightly. This is only really visible with wide apertures though.

[TheGreatDivorce]

Originally Posted by charlesking

Focus-and-recompose (using the centre point because it's always the best) is an absolute staple of good photography. Automated focus selection never works well, that's why manufacturers have spent so much on working out face-detection algorithms.

The one thing for which you need to watch out is that some lenses have a slightly curved focal plane, meaning that if you focus on something at the centre of the lens's field then rotate the camera so it's near the edge, the focus on that subject may shift slightly. If you have a static subject, it's always worth taking several shots, and even bracket the focus slightly. This is only really visible with wide apertures though.

Focus-recompose is absolutely the wrong thing to do with wide apertures and/or shallow DOF. It has less to do with curved focal planes than it does shifting the focal plane.

The best thing to do is choosing the focus point closest to what you want in focus, and work your composition into that.

With deep DOF focus-recompose is fine, though.

http://visual-vacations.com/Photogra...pose_sucks.htm