So I was reading this question and stumbled into part of an answer:
Actually, there were systems that used Green and Orange in the past,
but they were used to expand the range of the basic CMYK print, but
these days the pigments are so good that hexachrome system was closed.
I was a student when hexachrome came around and I’ve discussed it in class before now that I teach but, to be honest, I haven’t really seen it in use (other than a magazine I had that introduced the idea of hexachrome). I’ve had this discussion with colleagues before and no one really knows what happened to this technology.
How have the pigments changed? I’m sort of having problems understanding which properties of a pigment can improve to the extent that the extra inks could simply not be used (green, orange, and I believe violet was sometimes also included).
Were the costs for acquiring such a printing press too prohibitive for the different it actually makes? Was there a lack of support coming from the software? Is hexachrome widely used but I just live in some sort of isolated bubble? 🙂
ETA: Wikipedia says:
Hexachrome was discontinued by Pantone in 2008 when Adobe Systems
stopped supporting the HexWare plugin software.
But a quick search for CMYKOG printers suggests the technology still exists…
I know this is an old post, but it deserves some more info.
The reason Hexichrome was discontinued is multi-part, but all rooted to profit. It really didn’t die. It just changed form.
Hexichrome was first used primarily for fine art prints. (I think it was originally a proprietary technology, not Pantone technology.) Then someone realized that the extended gamut let them quite accurately reproduce a huge chunk of the Pantone spot library. Imagine what that does for ink sales.
Hexichrome was heavily licensed to head off abuse. That makes the market very narrow for Adobe who then decides it isn’t profitable to support the plugins. Hexichrome dies. Almost. Pantone sells Hexichrome to HP/Indigo.
Hexichrome becomes Indichrome. Indichrome adds Violet to the mix and can hit 90% of the Pantone library and gives Indigo a strong advantage over other digital machines.
Eventually it is reborn as Pantone XG, adding the V from Indichrome. XG is used for flat builds of Pantone colors for brand identity. XG is heavily used in package printing. By using the 5th unit for O, G, or V and coordinating color runs, a printer can reduce countless color changeovers to just three.
I am not aware of anyone using it for extended gamut within color images yet because of lack of application support. If that has changed, I would love to hear about it.