Printing Grey Colours

[Stuart Taylor]

Hi Phil

Greys or any neutral colour are notoriously difficult to manage, especially when dealing with "lighter" tones such as your background.

Quite often these can be further corrupted if there is a significant strong colour used elsewhere in the file that adds to the cast over the tint.

Our print guys don’t mess with the profiles to resolve individual colours such as these as each job could be different. We would normally start with the CMYK make up of the background colour and produce a strip of 4" squares/swatches of the original CMYK makeup and start reducing the Magenta by 2%, then another 2% on next one etc. You can also do the same with another strip by adding Cyan or reducing Yellow/Cyan if you have a green cast.

Our print manager has made up a master "pantone" chart for all of our printers and when trying to match up colours will refer to the CMYK chart printed off our own printers and then tweek one starting point until they hit the correct shade.

You will inevitably get slight shifts in colour from batch to batch of ink or even humidity etc can effect these more sensitive shades but with a little time spent making a custom swatch for this grey you should be able to lose the magenta cast.

Stuart

[Phill Fenton]

Thanks for the advice Stuart. The problem I’m having is across a range of files, not just this particular file so there’s no point in adjusting the grey in this file only. I’ve noticed for some time now that greys are printing warmer than before (more magenta) which is why I think the inks have altered since my original profiles were established. For this reason I think I need to alter the profiles themselves in order to compensate for what appears to be an inkset with a more dominant magenta. Does that make sense?

[Simon Worrall]

Phill
Are you using the Roland Colour System chart?
Along the bottom of this is a range of greys from white to black in 22 steps.
These put out pure black ink.
Simon.

[Phill Fenton]

I’m not using versaworks but will print of a pantone chart to check my calibration

[Phill Fenton]

I Printed some pantone colours and compared these to a pantone swatch this morning.

Last night I had tweaked a profile (but kept the original profile) – reducing the amount of magenta until the greys looked more natural. When compared to pantone greys there is a much closer match – but when compared to pantone reds the original profile is much more accurate. Looks like I’m going to have to alternate between profiles depending on the colours used in any prints – where there are greys I will use the new profile – but in all other cases revert back to the original profile…unless anyone has any better ideas?

[Chris Wool]

Quite probably the head and bi direction adjustments may be a bit off causing the colour shift as greys are made of all colours until about 70% then starts to use black.
I would double check these else you will be chasing around with profile settings for every shade of grey plus you said it’s changed recently

[Pane Talev]

On a similar note I’ve always had problem printing / matching the Pantone Cool Gray’s on a Mutoh Valujet 1204. Spent half a day doing and the result where bad. Gave up at the end.