output pngs to dark?


I have a piece of code which explicitly creates a 3 column array of red, green, blue values which I have scaled. For example
RGB = np.array( [ 10, 100, 180 ] ) etc.

Anyway, I use “savefig” to ouput it to a png image. The problem is that the PNG looks a lot darker than it should do, in fact if I output the RGB array as 3 frames and view it in another plotting software the colours are brighter. Has anyone come across something similar when outputting PNG images? I am sure this is something very obvious that I am missing.

Many thanks,