understanding exposure

[julie32]

hey guys

reading bryan peterson's book. I just need someone to explain something further...when he says to "expose for the blue sky", point your lens to the blue sky, get a reading, recompose and shoot....

Does this mean I have to shoot in M mode? What If I'm using AV mode and I've chosen an aperture of f8, when I get the exposure reading while pointing to the blue sky, when I bring the camera back down to shoot my scene (which in this base is a building), the shutterspeed changes...so what was the purpose of the sky reading?
I'm missing something very obvious here, but it's getting me confused.

I hope you understand what I'm asking here.....

thanks,
j

 

[Big Mike]

You are missing...Exposure lock. (or manual mode).

Check your manual...usually you can lock the exposure by holding the shutter button down halfway...or pressing another button. So you would aim at the sky, hold the button halfway to activate the meter, hold it there, recompose the shot and then press it the rest of the way.

With manual mode, you would aim at the sky, adjust the settings to get the 'needle' centred, then you can recompose and shoot anything you want and the exposure won't change unless you change it again.

 

[julie32]

Big Mike---you're big, you're mike and now you rock. thank you!

 

[DragonHeart]

You are missing...Exposure lock. (or manual mode).

Check your manual...usually you can lock the exposure by holding the shutter button down halfway...or pressing another button. So you would aim at the sky, hold the button halfway to activate the meter, hold it there, recompose the shot and then press it the rest of the way.

With manual mode, you would aim at the sky, adjust the settings to get the 'needle' centred, then you can recompose and shoot anything you want and the exposure won't change unless you change it again.

That is one of the most clear, concise, and plain english explanations I have *EVER* read.

 

[GC Jr]

LMAO Julie, your signature can have a COMPLETELY different meaning than what you intended it to be. Hint hint? :-D

I love shooting children!

LMAO

 

[MACollum]

You are missing...Exposure lock. (or manual mode).

Check your manual...usually you can lock the exposure by holding the shutter button down halfway...or pressing another button. So you would aim at the sky, hold the button halfway to activate the meter, hold it there, recompose the shot and then press it the rest of the way.

Doesn't this only work with MF? The focus also locks when you push the button halfway. If you're shooting with AF wouldn't you want to push the exposure lock button instead to only lock exposure and not the focus too?

This is something I was wondering about after reading Understanding Exposure, so thanks to the OP for bringing it up. I've never used the AE lock button before so maybe I should give it a try.

 

[Big Mike]

Doesn't this only work with MF? The focus also locks when you push the button halfway. If you're shooting with AF wouldn't you want to push the exposure lock button instead to only lock exposure and not the focus too?

It depends on how your camera is set up to lock exposure and focus. That's why the first thing I mentioned was to read the manual.

On my camera, I believe that the default is that the * button locks the exposure and the shutter button locks the focus. I have changed that so that the shutter button locks the exposure and the * button activates the focus (so I only have to release the * button to lock the focus).

 

[julie32]

GC Jr---- Oh I know it....about my signature...it wasn't an accident! Just kidding. Well sort of.