Yea, those two approaches are used for two slightly different purposes, and can even be mixed together. You get to a certain point in photoshop and use blending nodes for additional variations. There is definitely some overlap in what those two methods are capable of.

When I make stuff, the way I decide which method to use... I always ask myelf what it is I am try to accomplish, then use what is likely to give me a good balance of quality and file economy (considering package size and program performance).... and in case of supporting both, Poser and DS I have to consider program differences.

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Renderosity Store  Personal nick: Conniekat8
Hi, my name is "No, Bad Kitteh, NOO", what's yours?