TH2 Contour Axis Manipulation

How do I, in code, get access to the TPaletteAxis in a TH2 colz-style histogram?

I would like to manipulate the width of the color band so it doesn’t take up so much of the margin. Is this possible?

Also, is it possible to make axis number labels to appear in HEX without making a custom axis label?


TPaletteAxis palette =