As I thought, it's PORTRAIT ORIENTATION, not vertical.
In portrait orientation, the SB600 can still be pointed up to the ceiling, though it's the short side of the flash that's facing forward, not the usual broad side.
i fix a bounce card and it's still ok.
As catchlights mentioned, the flash is to the side of the lens, not above it. Just have to be careful that the lens doesn't cast any shadow.
please stop using the term "shoot vertical" if you're intending to describe shooting in portrait orientation. It's really confusing.
I don't know whether you really mean vertical (as in the lens is pointed vertically toward the ground or sky) or not.
45 degrees in what orientation?
An angle (eg. 45 degrees) means nothing without a frame of reference, an axis about which the angle is described.