On Sat, Jun 20, 2009 at 11:27 AM, yahvuu<[email protected]> wrote: > hi, > > Chris Mohler schrieb: >> Imagine I'm designing a black t-shirt with say five spot colors, >> including white. > [..] >> Whew ;) > > Whew, too ;) Makes me wonder if it has to be that hard or if > it points to some missing software improvements. Trying to understand > the example, i hope you don't mind some uninformed questions (and also > some out-of-sequence quoting). > > Besides anticipating printing press idiosyncrasies ('choke'), > it seems to me you're manually creating kind of a color separation. > Quite naively: doesn't photoshop know you're printing on black?
Yes - I end up doing a lot of it manually, and no it does not know - having a 'target' or 'base' would be a step forward. >> Here's my workflow for this in PS: I would use the (badly named) >> 'Apply Image' command to take the contents of each color plate and >> combine them into the white plate using the mode 'multiply'. > > this is to create the white underpinning, resp. the beginning thereof. > 'Apply Image' is short-hand for 'blend anything with anything', > but doesn't do any tricks that could not be achieved with layer stacks > in combination with proper channel masking. On track? Yes. > >> I would >> also manually "choke" the white plate - this means making the white >> areas a point or two smaller than the colored areas, thereby >> preventing the white from poking out at the edges of the colored >> areas. This process can get a bit tricky, especially if the original >> artwork is very complex. > > if the artwork was fully vectorized, say a pure inkscape job, > would that make things easier? Of course, but when photographic-type artwork comes into play, it's usually easier/faster to do the whole thing in a raster editor. > >> Often, create temporary layers (or plates), >> perform selection/drawing functions, then combine the result back into >> a plate in one of two ways - either making a selection on the temp >> layer and going to the plate and filling or erasing, or using the >> 'Apply Image' command to take the RGB channel of the current layer and >> combine it with a plate using a mode such as Multiply, Screen, or Add. > > i assume the temporary layers are mostly grayscale? Usually RGB layers, or grayscale channels. > the temporary layers serve as 'mixing stage' because it takes > several steps to create a desired mask, or is it more > to keep selections/drawings for reuse? A little of both. Sometimes I just need a very complex selection, but I need to do some work to create the selection. Other times I need to store a selection for later use (that's generally when I make an extra channel). After re-reading the notes on the talk, if we have a Layer->Plate mapping, I think that will cover most situations. I would prefer a way to "mix" the plates, and to be able to add new layers that could later be applied to new or existing plates, but this could be worked around. Chris _______________________________________________ Gimp-developer mailing list [email protected] https://lists.XCF.Berkeley.EDU/mailman/listinfo/gimp-developer
