7-Color Process

[gordo]

Gordon, I would also think that printing with a fixed palette would also tend to result in much lower coverages on average for each print unit since more inks could be used to get to a specific target. Have you found this to be true or does is it not a significant factor?

I don't think it's significant.
You won't have more than three chromatic inks printed in an area at any given time - just like process. If you reduce/eliminate, for example M and Y in an area, and replace it with O then process is lower but spot is higher. I think it's six of one.

 

[Macmann]

The biggest obstacle is changing the designer's and print buyer's minds. If their client's company logo has been Pantone 192 and Pantone 185 for the last 30 years, it's tough to convince them you'll match it on press with this cool new printing process-anyone remember Hexachrome? As a side note I find it interesting that Esko and Pantone as well as XRite are all owned by the same parent corporation.

 

[gordo]

The biggest obstacle is changing the designer's and print buyer's minds. If their client's company logo has been Pantone 192 and Pantone 185 for the last 30 years, it's tough to convince them you'll match it on press with this cool new printing process-anyone remember Hexachrome? As a side note I find it interesting that Esko and Pantone as well as XRite are all owned by the same parent corporation.

Having been a marketer of such a solution I would have to somewhat disagree.
A properly designed solution is transparent to the designer. I.e. they continue specifying spot colors as they have done in the past.
The buyers certainly deserve some blame - at least the major volume buyers because they can require that their suppliers adopt the technology. But the biggest barrier, IMHO, are the printshops. They are typically not marketing savvy. As a general rule, they do not develop or provide solutions designed to help their print buying customers achieve a better result. Most printshops are reactive rather than proactive. If the customers asks for something different they may respond - otherwise they'll just keep doing the same thing over and over.

 

[chevalier]

Having been a marketer of such a solution I would have to somewhat disagree.
A properly designed solution is transparent to the designer. I.e. they continue specifying spot colors as they have done in the past.
The buyer's certainly deserve some blame - at least the major volume buyers because they can require that their suppliers adopt the technology. But the biggest barrier, IMHO, are the printshops. They are typically not marketing savvy. As a general rule, they do not develop or provide solutions designed to help their print buying customers achieve a better result. Most printshops are reactive rather than proactive. If the customers asks for something different they may respond - otherwise they'll just keep doing the same thing over and over.

You're absolutely right. You've got to produce samples showing what your process can achieve with spot color accuracy. I've tried in vain many times to push to get jobs quoted two ways: with brand colors, with "special printshop brandname" process. Let the buyers speak with their purchase orders. In my experience the purchasing department always overrides brand management and the artwork departments when it comes to packaging.

 

[bobbyc]

I don't think it's significant.
You won't have more than three chromatic inks printed in an area at any given time - just like process. If you reduce/eliminate, for example M and Y in an area, and replace it with O then process is lower but spot is higher. I think it's six of one.

Some graduate student research conducted at Clemson University showed approximately 12-18% less ink consumption, based on 600 equally distributed PMS colors (in each color sector). These colors printed 7C were also more stable when subject to systematic overimpression (increasing dot gain) compared to a 4C mix.

 

[gordo]

Some graduate student research conducted at Clemson University showed approximately 12-18% less ink consumption, based on 600 equally distributed PMS colors (in each color sector). These colors printed 7C were also more stable when subject to systematic overimpression (increasing dot gain) compared to a 4C mix.

Do you have a link to that study or a PDF of it? I suspect something else is going on.

When you say "systematic overimpression (increasing dot gain) compared to a 4C mix" are you referring to flexo or offset?

What ink does "12-18% less ink consumption" refer to?

 

[bobbyc]

Do you have a link to that study or a PDF of it? I suspect something else is going on.

When you say "systematic overimpression (increasing dot gain) compared to a 4C mix" are you referring to flexo or offset?

What ink does "12-18% less ink consumption" refer to?

Unfortunately not published as a paper yet -- the student went and took a job (making money?!?). He has presented the data at several conferences, though. Hopefully there will be a published thesis one day...

This was flexo -- colors were printed 4C and 7C side-by-side, then dot gain was increased by increasing impression one station at a time.

Press was profiled, then the 600 sample colors were processed as either 4C or 7C builds. The "12-18% less ink consumption" refers to the average amount of TAC for each build. For instance, maybe 220% TAC need to produce a color with 4C vs 198% needed with 7C. Largest variation in TAC obviously near the extended colors -- 100% Orange vs 100Y + 60M.

 

[Correct Color]

Gordo,

I don't think it's significant.
You won't have more than three chromatic inks printed in an area at any given time - just like process. If you reduce/eliminate, for example M and Y in an area, and replace it with O then process is lower but spot is higher. I think it's six of one.

You're absolutely correct, or at least you should be. N-Color or Hi-Fi inksets --as they are also known -- are not at all uncommon in large format printing. In fact they're pretty much standard in high-end fine-art aqueous machines these days. Also there are several weird color combinations that have been tried in fabric printing. So I've profiled any number of ink configurations over the years, and interestingly, whatever the inkset, I always confine the total ink limit on my patch sets to 400%, and then the profile itself to something under 400%, depending upon conditions, regardless of the colors in the inkset. Because the key thing to keep in mind is that if you can get to any color with C,M, and Y, then there's no reason to bring in the other colors to do it. They are only used to extend gamut out into areas where combinations of C, M and Y will not go, and should only be brought in in areas ramping into those colors.

Of course all settings are up to the individual profiler, so it's certainly possible to build up a muddy four-or-more color mess in some mid- to 3/4 tone colors, but it shouldn't be done, and it serves no purpose.


Mike Adams
Correct Color

 

[gordo]

Unfortunately not published as a paper yet -- the student went and took a job (making money?!?). He has presented the data at several conferences, though. Hopefully there will be a published thesis one day...

This was flexo -- colors were printed 4C and 7C side-by-side, then dot gain was increased by increasing impression one station at a time.

Press was profiled, then the 600 sample colors were processed as either 4C or 7C builds. The "12-18% less ink consumption" refers to the average amount of TAC for each build. For instance, maybe 220% TAC need to produce a color with 4C vs 198% needed with 7C. Largest variation in TAC obviously near the extended colors -- 100% Orange vs 100Y + 60M.

Thanks, that clarifies it. How I read it is that the "12-18% less ink consumption" is not necessarily the total volume of ink being used for the job being reduced. It's just that the use of the spot color in place of the process color has reduced the TAC in that area like the 100% Orange vs 100Y + 60M example you gave.
I think I saw a bit of that study (or a similar one) which showed that the stability of the spot color simulation using process screen tint builds was pretty much the same as the stability of color just using a single spot color in a flexo environment. That was tested by increasing the impression pressure (dot gain).