>wouldnt the bracketing function only bracket for the exposure >i expose for first the over and under expose that???
By default, yes. However, you can setup the bracketting to be all in one direction if you want. See the exposure/bracketing section of the manual.
>im thinking to expose for the sky then using the same focus >points expose for the tree or somethign similar without having >to refocus or touch anything else (not sure how to do this >though) then combine it together
Using spot metering or center-weighted you can set the exposure, lock it, then focus and recompose; repeat for each exposure difference.
It would probably be easier to check the metering at your multiple points, then either bracket the exposure manually or automatically. One advantage to the autobracketing is that when the camera is in continuous release mode (CL or CH), it will take all of the shots in the bracketing sequence then stop when you hold down the shutter release.
>if its not worth the effort or you think im talking rubbish >then let me know as this is somethign i havent dont before and >am only getting to know the camera properly so i dont want to >blow my chances of getting a good picture while on holidays
Don't underestimate the accuracy of the camera's matrix metering.
---------+---------+---------+---------+ Joseph K Seattle, WA, USA