Gradient, banding and clipping

Gradient refers to the homogeneity of the picture when shooting above the X-sync.
Gear optimized for Hi-Sync, such as the Quadra HS head, limits this gradient effect.
With gear compatible with HSS, this gradient effect doesn’t exist.

Clipping and banding are the same.
Banding is the black band on the picture that occurs without Hi-Sync or HSS technology.
The light out of flash is not synchronized correctly to shutter speed and creates that black band.