Flashes etc.

[Big Mike]

The asterisk button...is set to FEL (flash exposure lock).
As for the on switch, the first click (on) turns the camera on but disables the thumb wheel on the back (for shooting control)...this is so you don't accidentally adjust something. The 2nd click (I call it the hockey stick) activates the thumb wheel for exposure control (depends on the mode you are in).

All this stuff is in the manual...and I usually recommend that people read it through, 3 or 4 times, to let all that stuff sink in.

 

[Ptyler22]

Ya, thanks, mike. I did try and read the manual but alot of the things aren't explained to well.
In what situation would someone want to use FEL? I ask because I don't have any idea what that is

 

[Big Mike]

The flash uses a 'pre-flash' to determine how much power it's going to need. So when you trip the shutter, the flash fires a very quick pre-flash, reads the light that comes back, then fires it again at the power needed. It's so fast, you probably don't notice it.

So when you use the FEL, it fires the preflash and reads the light....it then holds that power setting for the upcoming shot. The flash metering is centre weighted, so if you wanted to have your subject off to the side of the composition, but wanted to light them up with flash, you could use FEL to lock the flash exposure as if they were in the centre of the frame, then recompose the shot and fire.

Really, it's not something that a lot of people use. You can probably change the function of that button, if you want.

On my cameras, I have the * button set to activate the auto focus, rather than using the shutter release button. However, I believe that the 40D has an additional button for AF, right beside the * button.

 

[Ptyler22]

The flash uses a 'pre-flash' to determine how much power it's going to need. So when you trip the shutter, the flash fires a very quick pre-flash, reads the light that comes back, then fires it again at the power needed. It's so fast, you probably don't notice it.

So when you use the FEL, it fires the preflash and reads the light....it then holds that power setting for the upcoming shot. The flash metering is centre weighted, so if you wanted to have your subject off to the side of the composition, but wanted to light them up with flash, you could use FEL to lock the flash exposure as if they were in the centre of the frame, then recompose the shot and fire.

Really, it's not something that a lot of people use. You can probably change the function of that button, if you want.

On my cameras, I have the * button set to activate the auto focus, rather than using the shutter release button. However, I believe that the 40D has an additional button for AF, right beside the * button.

Yep it does have another AF button and it is right beside the * button.
I don't know if I will ever use that FEL button other than for a strobe, when I want to piss people off, lol, but I will try it out like you said, who knows maybe it's a new fad, but I doubt it. haha Thanks Mike