recomposing?

Hey all

If I am in M, TV or AV mode on a 50d, how do I focus and lock it then recompose my pic.(Say focus on the eye of a child for portrait then back out a bit) Looking in the manual it explains it but for program or basic modes unless I missed something. I currently use the * for AF when shooting sports. Sorry if it's a really "noobie" question.

Randy

if using the shutter for AF, have it in one-shot mode, half-press the shutter, hold it, and recompose. If using *, just press it to focus and then release. The focus won't change until you press * again.

keep in mind, if you focus on someones eye, and walk back, you will no longer be focused on the eye, but rather in front of the persons eye (or in other words, the focus point has moved back however much of a distance you walked back)

also: even if you do not move front/sidesways/backwa​rds, but say focus on someones eye, then tilt your camera to "recompose" your framing/shot, you will no longer be 100% focused on your original focus point. how much the focus is effected depends on your apeture/distance your shooting at.

here is a link that describes it better: http://visual-vacations.com …focus-recompose_sucks.htm

thanks for the quick replies1 I was thinking about this with a zoom lens as opposed to stepping forward or backward - does it change things?

you mean focusing at a set zoom, and then zooming out and shooting? if thats what you meant, then i believe your focus will be messed up as well.

why would you want to do that anyways?

Also note that, unless you have changed it in the custom functions, your exposure is also locked with half-press of the shutter.

Hang on, you use '*' to focus? Is that in ADDITION to the shutter being AF, or have you separated AF from the shutter? If it is just duplicating the shutter, then I think you have to hold the * while you recompose. If it is separate, then by hitting * and releasing, it is locked.

With many zoom lenses, if you change the focal length you'll need to refocus. Only a parfocal lens will do as you describe>>> http://en.wikipedia.or​g/wiki/Parfocal_lens

i have never got a good shot recomposing i say stay away from it idk why so many people do it

jcp2000 wrote in post #7426569
i have never got a good shot recomposing i say stay away from it idk why so many people do it

Possibly because they do get good shots recomposing

neil_r wrote in post #7426598
Possibly because the do get good shots recomposing

do you mean they....

jcp2000 wrote in post #7426610
do you mean they....

possibly

Unless you're shooting stopped down, you'll often lose pin-point focus accuracy by focus then recomposing. It's generally a bad technique and I'd argue you'd be better off not using it at all. You have a 50D which offers an excellent, intuitive and quick method of switching auto-focus points - via. the joystick you toggle with your thumb.

habenero wrote in post #7426352
Say focus on the eye of a child for portrait then back out a bit

If by 'back out', you mean 'zoom out', then that's a definite no-no.

Or just frame it first and manual focus.