I'm having a bit of a trouble to obtain kakhi or Vallejo's English Uniform with oils. Can anyone give me a helping hand with this (and thr darlen and lighten it)?
Personally, I'd start with yellow ochre, adding raw umber for shadows and white for highlihgts. You should be able to get a nice medium khaki with about 3 parts orchre, 1 part raw umber and 1 or 2 parts white. More white for highlights, more umber for shadows. HTH,
For Khaki in acrylics a mix of "deep violet" and "cadmium yellow deep" on a ratio 2:1 will give a dark greenish khaki while a ratio of 1:2 will give a mid tone khaki. For lighter desert colours try "deep violet", "titanium white" and "cadmium yellow deep" on a ratio of 1:2:3; 1:4:3 or 1:8:3 using more "titanium white" for even lighter tones.