hm... guess i'll try that,
but i got the blue-green i wanted using the base I have... problem seems to be more that the camera's color sensitivity and the human eye are not the same...
Use a dark green base-coat under blue-green, so that the green doesn't get lost. Blue, being a primary colour, will tend to dominate, even in mixes. If the green base is more pronounced, it will show more clearly in photographs.