There is one already. If it isn't included in Poser, then it's here in Free Stuff. Originally used to change the default flesh colour on early models to something more suitable for texture use :)

I think it's called All White or something :)

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You just can't put the words "Poserites" and "happy" in the same sentence - didn't you know that? LaurieA
  Using Poser since 2002. Currently at Version 11.1 - Win 10.