Select an object. > Modify panel > Modifier List > VertexPaint > VertexPaint Paintbox > Click the Adjust Color button.
Select an object. > Modifiers menu > Mesh Editing > Vertex Paint > VertexPaint Paintbox > Click the Adjust Color button.
Select an object. > Utilities panel > More > Assign Vertex Colors > Click Assign to Selected > Modify panel > Modifier List
> VertexPaint > VertexPaint Paintbox > Click the Adjust Color button.
The Adjust Color dialog lets you adjust the color of currently selected vertices. If there is no active vertex sub-object selection, it affects all vertices equally.

See Red, Green, Blue / Hue, Saturation, Value.
Preview—When on, vertex color adjustments are previewed interactively in shaded viewports (provided that on the Paintbox, Vertex Color Display - Unshaded or Vertex Color Display - Shaded is active). Default=on.
Contrast slider—Lets you adjust the contrast of the vertex colors.
Histogram—Graphically shows the distribution of colors in the vertex selection, as well as the current shadow, gamma, and highlight input levels.
The shadow, gamma, and highlight input levels can help you adjust 3ds Max viewport color to better match your target hardware display (such as a game engine).
Shadow level—Adjusts the level of shadow display.
Gamma level—Adjusts the gamma display. This value is a gamma correction value.
Highlight level—Adjusts the level of highlight display.
When you adjust a level, the corresponding arrow moves on the histogram, to indicate the current setting. (However, you can't graphically drag the arrows.)