Newbe needs advice please

[Menkaure]

I have a Canon Rebel xt and a Canon Speedlight 580EX. I normally shoot in "P" mode so I have some control and some auto. Daylight pics are no problem but my new Speedlight has me confused.

These pics were both shot at 1/60 second, F3.5, Focal length 18mm, ISO 200.
I was trying all kind of settings and flash combinations but the hall was messing me up because the walls were so far away. (Bounce Flash)
Anyway... Both of these pics were taken with the same settings. Why are they different and why can't I get a good flash shot? Keep in mind I'm just starting with this flash.
Thank you for looking.

Menkaure

[feilb]

You may want to post this over in the flash forum not on the C&C forum.

[FREEZE]

i'm not a pro by any stretch but i think the difference may be where you metered the shot.On the forst one you may have metered at a brighter spot and the flash doesen't think you need as much light as if you metered on say one of the shadows.Hope this make's sense pros please correct me if i'm wrong.

[goforphoto]

Were you bouncing straight up or did you have a diffuser to deflect the light forwards as well as up to the ceiling?