Create a greyscale step gradient

I need to create a greyscale step ramp gradient for use as a map in after effects.

I was hoping there was some automated way to do this. I don't think I could find it in the actions palate.
Thanks in advance.

John Rich

Use gradient tool, in grayscale, whit to black. Then Adjustments > posterize.

You may also want to set smoothness to zero to get a linearly interpolated ramp.

And probably the gradient fill layer as well.

Thanks guys. That's really a big help to me.

John Rich