Hmm - wouldn’t this correspond to a matrix space with CIE xy primaries of 1/0, 0/1 and 0/0,
which can be created via Photoshop’s Custom profile function (for some reasons integer value are not allowed):
Red: x= 0,9999, y= 0.0001
Green: x= 0.0001, y= 0.9999
Blue: x= 0.0001, y= 0.0001
Peter
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