Confused about Exposure Lock

[jcspenny]

Hello everybody. I am kind of confused when it comes to exposure lock. I have a Canon Rebel XS and shoot on partial metering.

I know to start I need to set the focus point I want to use and half press the shutter button on the spot I want to meter off of. This is where I get confused. Do I press and hold the * button, or do I press and release it? And then, do I release the shutter button, recompose, and half press on what I want to focus on, or do I keep the shutter button half pressed? Or am I even more confused than I thought I was and none of that is anywhere near correct?

Any advice is greatly appreciated. Thanks, guys!

[Vagebond]

Hi,

1. You press and release the * to lock exposure, and you'll see the * on the left in your view finder. Exposure is locked for as long as you keep the shutter button half pressed.

If you release the shutter button, that exposure is kept locked for about four seconds.

If you half press the shutter button after releasing it but before the end of the 4 seconds, exposure stays locked (* in viewfinder) and the lens is focused if it's not on manual focus.

Take a shot, and the 4 seconds are counted down again, half press again and it stays locked longer.

This way you can take several shots with the same exposure, focusing for each shot.

2. You didn't ask, but you might be interested in changing the function of the * button to "focus". This should be somewhere in the custom function menu, " AE/ AF lock" button. If you activate this, you focus by pressing the * button and you lock exposure by half-pressing the shutter button. It has its uses.

I hope I haven't confused matters even more instead of helping

[RecurrentNerve]

I always found the default setting for this on my Nikon to be a little confusing; I have now set it so that you press it once and it locks the exposure til you press it again. Keeps things simple - get light reading, lock it. Focus is entirely separate. Perhaps your Rebel has a similar setting?

[Vagebond]

I can't find a Rebel equivalent to what you described, RecurrentNerve. I guess manual exposure is the way to go on the Rebel if you really want to lock exposure forever without pressing a button every 3 or 4 seconds

I forgot to mention in example 1. of my post that by pressing * again, even while * is still active, the meter sets a and locks new exposure values.

[inkista]

Two articles to look at at the Canon Digital Learning center website:

Using Auto Exposure Lock

and

Back-Button Auto Focus Explained

Those two in combination more or less cover all the stuff you can do with the * button. Including how to take AF start/stop off the half-press of the shutter button to separate it from the AE stuff.

[jcspenny]

Thank you, everyone! I think I understand it now.