Question about using "*" for focus

edit: I read the AF * thread, and I think it answered my question, but that still stinks that you can't lock the exposure.

I like the idea of using the * button to autofocus, but I think I'm missing something. I was trying to do some panoramic shots yesterday, which requires exposure lock. So, I set my custom function to allow the * button to be AF and the shutter button to me AE lock. However, with this setup, how can you use AE lock?

Originally, I wanted to use single-shot drive mode. Well, if you depress the shutter halfway, it locks the exposure (good). So, I take the shot, and then recompose with holding the shutter half-way down to keep the exposure locked. Since I'm in single-shot drive mode, I can't shoot again until I completely let up on the shutter, which unlocks the exposure, which defeats the purpose of having exposure lock on the shutter button entirely.

OK, so I change it to drive mode. Well, this works, but I don't want to shoot at 5fps because it fires 2 or 3 times every time I depress the shutter, which is also not what I want. It's also prone to accidentally letting the shutter up too far, which in turn unlocks your exposure.

Basically, I was wondering is there was a way to use AF on the "*" button, and still have access to exposure lock. I know I can take an exposure reading and then change it to manual, but that is kind of a pain, plus I can't meter different parts of the shot very easily as lighting conditions change.

From what I understand, the best exposure method for pano's is to use manual.

Read this thread, i think it will help
https://photography-on-the.net/forum/showthre​ad.php?t=247494

Chris - for panos, you really ought to be in manual exposure, and manual white balance. Take meter readings thru the whole scene, and figure out the best overall exposure, dial it in, and shoot.

a nice thing about * focus is that once you take your finger off the * button the focus doesn't change -- otherwise for a pano, you'd also have to put your lens in MF -- one step saved.

For panoramics, I would simply use manual exposure mode.

Actually, I use manual exposure more often than not anyhow - along with the Custom Function 4 set to 1 (for the autoexposure being controlled by the * button). I like to take control of my camera, rather than having it decide things for me.

Yeah, after reading I'm beginning to get that impression too. Well, darn. Thanks anyways!

I tried using the * button but just couldn't get used to it and am back to the conventional method. I guess old habits die hard.

Liza, it's not that much the old habits, but it's more like the shooting situation that require to use one mode or another. I'm now on CFn4=0, but there are times when separating focus from exposure is needed, and having the possibility to do it is really welcomed.

I used the * for focus today, as I was in a situation with some moving subjects and static shots in between...worked very well. I don't like it for architecture photography, which I do a lot of, but for people in an event situation, it was very nice.

A couple of observations: First, in single-shot drive mode, you don't have to let up all the way to take another shot. You can go from full-press to half-press, recompose, and full-press again. If you're in CF4-1, you'll keep your exposure locked.

Second, full drive mode is actually a great way to take panoramas. This was discovered by a guy over on the G-series forum (sorry, I forget who gets the credit). Just press the shutter and swing the camera; when you get to the pano-stitching stage you can choose to discard extra shots. This is a huge time-saver, and also makes it much easier to get panos that contain moving objects. (An additional hint is to swing against the primary direction of motion when possible.)

On my 20D, it does not allow me to take another shot until I have fully released the shutter button. If I release it halfway, it will not allow me to take another shot until I completely let up on it.

Also, swinging the camera may work in the right conditions, but when I did that I got a lot of motion blur. I shoot handheld, so swinging the camera around at 1/500th causes a significant degree of softness.

liza wrote in post #2380978
I tried using the * button but just couldn't get used to it and am back to the conventional method. I guess old habits die hard.

And I thought I was the only one

much prefer exposure lock on the * button