Printing White Under CMYK

[NZOC]

Hi all,

When printing white under CMYK, for example on black material, we always end up with the white showing slightly around the edges of the text or image.

Is there a way for that white to print slightly smaller than the top colour to avoid this? Unfortunately its not as simple as reducing the size and printing the white layer in a separate pass first as for more complicated shapes, like text, the inner areas also shrink and will actually show more white there (hard to explain but hopefully its clear enough!)

We are working on Adobe Illustrator and using Cadera RIP software.

 

[dweavers]

Easy as, copy the cymk image, create a new layer (white) lock the colour layer, make sure you are now in the white created layer then paste in front, fill with white as per your white ink swatch, then either offset the path with a negative value (say -.1mm) then delete the original pasted image which will leave you a slighlty smaller white.
Or you could simlpy add bleed to the cmyk layer with the fill/stroke (using stroke of say .25 pt)
You will get better registartion if you do the white-cmyk in one pass.

 

[dweavers]

 

[dweavers]

give me a call Im in Christchurch 0274288342

 

[SignMeUpGraphics]

Can you adjust the trap in Caldera?
You should be able to pull the white back a tiny bit.

 

[chinaski]

See my screenshot. Use the adjust option to reduce White.

It will take the border of where-ever you are printing white and reduce it. Even -0,1mm is adequate for white underlay for text.

 

[johnnysigns]

We use Onyx Thrive to rip our files and you can negatively trap the white by however many pixels beneath the CMYK output. The real problem is your head alignment though. The white is out of calibration relating to your color channels.

 

[signheremd]

Hi all,

When printing white under CMYK, for example on black material, we always end up with the white showing slightly around the edges of the text or image.

Is there a way for that white to print slightly smaller than the top colour to avoid this? Unfortunately its not as simple as reducing the size and printing the white layer in a separate pass first as for more complicated shapes, like text, the inner areas also shrink and will actually show more white there (hard to explain but hopefully its clear enough!)

We are working on Adobe Illustrator and using Cadera RIP software.

You can trap the white. You can do it manually by creating a file for it or in your RIP or Print software (many offer this feature). We use Onyx on a FluidColor printer which uses TopHand print software and we can do it there. Other than that, time for a calibration on your printer.

 

[Martin Lehmann Madsen]

Hi!
You can do that in Onyx Thrive Job Editor/Color correction/Tools/Spot layer tool:

 

[johnnysigns]

Negative is trapping inside and positive would be trapping outside the color. On our flatbed we ran between -2 to -4 pixels.

 

[Pauly]

Hi!
You can do that in Onyx Thrive Job Editor/Color correction/Tools/Spot layer tool: View attachment 158009

That only works when onyx generates the spot layers.

If you did them yourself in illustrator or photoshop, i dont believe onyx allows you to choke/spread the spot channel.