Illustrator / Preflight colours don't match!

[Chasez]

Hey all,

I'm running into an issue I have never seen before. I have a file in illustrator (CS6) with the only colour being black @ %30, when I print the PDF and open in onyx (10.2.5) and preflight, under the color correction the colours show as using all CMYK. Is there a reason for this, or does anyone know why it has changed the colours? Here is the file in illustrator and in prefight,

Hope someone has an answer... this is a sample for a large job!

Chaz

 

[J Hill Designs]

the RIP is set to convert to CMYK using the profile.

turn off color correction for a quick fix,

or (if you can) tell it to print in K only mode instead of CMYK

 

[dypinc]

Are you sure your source profile in Onyx matches your working space profile in Illustrator?

Then if you want to only use black ink you need to make sure Onyx is set to use inkjet black only.

 

[Chasez]

the RIP is set to convert to CMYK using the profile.

turn off color correction for a quick fix,

or (if you can) tell it to print in K only mode instead of CMYK

Just turned off all ICC profiles, and the CMY are all set to 0 now, but K is not at 76, not 30 and color correction is greyed out.
Unless I missed something?

Chaz

 

[Chasez]

Are you sure your source profile in Onyx matches your working space profile in Illustrator?

Then if you want to only use black ink you need to make sure Onyx is set to use inkjet black only.

Where in Onyx do I check this?

Chaz

 

[neil_se]

That's what the RIP is there to do, match the printer's output with the result you're expecting. Just because your file says 30% K, doesn't mean that the printhead will output 30% of it's maximum. Linearisation dictates how much it needs to output to achieve a smooth gradient from nothing to solid black.

 

[Bly]

That's what the RIP is there to do, match the printer's output with the result you're expecting. Just because your file says 30% K, doesn't mean that the printhead will output 30% of it's maximum. Linearisation dictates how much it needs to output to achieve a smooth gradient from nothing to solid black.

Exactly. And if you have a custom profile properly linearised the output will be a neutral CMYK grey, matching 30% black.

 

[dypinc]

Exactly. And if you have a custom profile properly linearised the output will be a neutral CMYK grey, matching 30% black.

Sure, if that is what you want it to do. But most RIPs also give you the option to print black only.

 

[eahicks]

I think you would only want to print with K if you are doing color separations, not to achieve a grey.

 

[Bly]

Sure, if that is what you want it to do. But most RIPs also give you the option to print black only.

Sure, if you want a thin, banding black.

 

[dypinc]

Sure, if you want a thin, banding black.

I suppose with some printer yes, and with some printers no. Some printers like the latex printers, black looks much richer if you print 100% inkjet black instead of a CMed black.

 

[Bly]

How would your method work with this image?

 

[dypinc]

How would your method work with this image?

As an sRGB profile is assigned to this image and everything but the Apple is neutral, yes you could print using black only for everything but the apple. Not saying all RIPs can do though.

As an example if I was printing with RIP to a Canon iPF printer as a halftone device it could print beautiful using only the grays and black ink for the grayscale part of this image. Of course that would depend on the capabilities of the RIP being used.

Whether it is necessary to do that depends on what output you want to achieve.