Hi, I need to be able to convert from a larger working space like Adobe RGB or ProPhoto RGB to sRGB and I would like to do it using a Perceptual mapping (which isn't possible directly as only a Relative Colorimetric mapping is available between working spaces). Is it possible to construct a table-based profile to map to an intermediate image file, so that I can do a Perceptual map to this image file and then a RC mapping to sRGB? If it is, then how would I go about making this profile using Argyll? Ideally I would like the same profile for the forward and reverse mapping. If at all possible I would like to be able to do this mathematically, rather than by trying to scan from color spots from my monitor ... or something like that! Help much appreciated!! Robert