focus lock and exposure lock

[arunap]

Has anyone tried to do both focus lock and exposure lock at the same time? i have a canon rebel and it lets me chose either one of the options at one time, but not both.

[KeithAlanK]

Not sure why you might need both for the same photo.
Locking both shutter and exposure doesn't offer a logical advantage that can't be achieved any number of other ways.

The button is a convenience feature for people who routinely shoot with plenty of automatic help, in order to force the camera to do what's desired like focus on something at the edge of the frame, without going to manual focus.
Exposure lock is handy for seeing where the maximum effect happens when rotating a polarizing filter, or for getting a good exposure of the sky when silhouetting a subject, among other uses.
These are just a few examples.

Each has their place, but if you feel you need both it's probably easier to just shoot with manual exposure (or shutter/aperture priority) and/or manual focus.
If using both shutter-lock and exposure-lock at the same time was a desired feature, you can bet that this would have been noticed by the manufacturers by now.

[Daniel Bates]

Are you talking about the * button? If so, I use it regularly... but I shoot M so AE-lock doesn't really do anything for me.

[engstrom]

Of course the default behavior is to have focus lock AND exposure lock tied to the half press of the shutter button. Why won't that work?

[Gordon]

Exposure lock by default is tied to the '*' isn't it ? You just don't 'normally' use exposure lock. The default is to have focus on the half press and exposure lock on the rear button. If you don't exposure lock, the camera meters when you shoot.

[arunap]

Thanks for the useful suggestions. So let me try going Manual to get the right focus and set a * (exposure lock) on the subject. I guess that should solve both my focus and exposure lock problem.
To state my problem clearly, my canon rebel has one settings for focus lock and another * for exposure lock. Focus lock makes sure that the main subject is in focus when you finally recompose and take the shot. Exposure lock makes sure that your system is not fooled by the surrounding lightning. So I thought why not have them both for a given scenario; hence the question. It didn’t occur to me to go manual and try the exposure lock. So let me try.

Thanks all.