On Sat, Jun 20, 2009 at 11:27 AM, yahvuu<yahvuu@xxxxxxxxx> 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'susually 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, butI need to do some work to create the selection. Other times I need tostore a selection for later use (that's generally when I make anextra channel).
After re-reading the notes on the talk, if we have a Layer->Platemapping, I think that will cover most situations. I would prefer away to "mix" the plates, and to be able to add new layers that couldlater be applied to new or existing plates, but this could be workedaround.
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