If you are using Graphix Advantage or Omega, you currently have two options available if you are wanting to remain within the Gerber software; output as a single color gradient or a process job. If going process, you can elect to output using only CMY forgoing the B, or use the traditional CMYK structure. If electing CMY output only, be sure to change your color correction so that the use of CMY will represent Black more appropriately.
If you are using SignLab e6.1 with the thermal module, you have the ability to output using one, two, three, or four colors of your choosing (along with other options in the design or output areas) by taking advantage of the “Multitone Bitmap” feature. (Actually, it could up to eight spot colors if using Dutones as your selected colors, but that can be addressed later.) This is one of the reasons this feature is included and intended for. I’ve been experimenting with this feature again recently and have produced some neat prints that aren’t easily achievable within Gerber’s software.
Your other option would be to use a “painting” program like Photoshop or PhotoPaint to separate your image into “two” images. There are multiple ways of doing this with some more appropriate then others depending on the image. In the big picture, you want to create a “Black” image and a “Blue” image file. Within Gerber’s software, you can then assign each image to be rendered with a single color and elect to Overprint one of the images for your desired result.
Rushing through this, so please ask for clarification if needed.
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Phill,
Get a hold of a SignLab e6.1 demo. You can make the ole ColorCAMM sing a completely different tune then what it can currently do. The Multitone Bitmap feature mentioned above is just one of a plethora of offerings. 🙂