convert an colour image to greyscale-like image

[justask]

Hello!

How can I convert an colour image to an image with shades of a given colour (brown, red, ...)?
This procedure is similar to greyscaling (shades of grey).
I tried the duotone built-in function, but there is only two colours.

Thanks

[Antonio]

Menu Adjust > Hue variation

[justask]

Thank you very much for your reply. It seems the simple matters can sometimes cause big problems for me.