Night setting

[vuser]

Hi, find it strange, any advise.
I am using 450D to try out the P and M mode in the night time.
In P mode, with 580II on, the setting is f2.8 and 1/60, exposure is auto at "0", fix ISO at 400.
But why, when in M mode, if I will to set f2.8 and 1/60 , the exposure is at extreme left,if I just shhot, the picture came out to be the same as mode P???

???:

 

[J-Chan]

welcome to the world of flash photography..

I'll try to make things simple.. P mode the cam determines the exposure, so the needle is for you to indicate whether you want the cam to under or overexpose the pic, in this case the shutter is limited to 1/60 by default when using flash.. without the flash attached you would get a much slower shutter speed..
M mode you determine the exposure via inputing values, but the cam meters for the ambient light according to the values given so if you didn't use flash the pic would be underexposed as suggested by the needle at the extreme left.. but of cos with flash added, the cam does its magic using E-TTL to get the correct output level for the flash, thus correctly exposed..

 

[vuser]

Hi, Thanks J-Chan.
So u mean when in M mode, with the flash turn on, if u enter both value of shutter and aperture (according to what u get from P mode), the exposure meter will still show extreme left , until the picture is taken, it will be same result as what in P mode is taken, meaning in the M mode, the exposure meter will not adjust (in according to where Flash been turn on)...is that you u mean???
BTW, normally what mode u use to take portrait at night or low light??

 

[J-Chan]

the manual explains alot about what the modes do if you had read it..