Grey/ gradient issue

[c.march]

Hello everyone, I'm back again with another question. I'm trying to better understand what is causing this issue. Our client uses a 3rd party design company who supplies us with PDF's, Sometimes I'm able to take the pdf straight into VW and print it. Sometimes it's too large of a file and gives me an insufficient memory error. Anyway, when that happens I save their pdf from PS as a tiff and I discard layers. my media I'm printing on is roland brand backlit. using profile - Roland DGA GBF for the glossy backlit signs. Preset is set to Pre-Press General, the target profiles are AdobeRGB1998 and CMYK is USWebCoatedSWOP. Raster and Vector are both Colorimetric. I've changed the raster to Preceptual which made no change to my print. Use Embedded ICC profile was checked.

I then informed the 3rd party that I could see banding on their pdf, in my VW rip preview, and in the actual print. I've since received the native file which was done with InDesign. When I open the file up with indesign, I see they have 2 different rectangles making their gradient. One being 19%k The second when I clicked it, showed up as an rgb value. and had 0%k. Lastly if I check the color settings on their native file the working space for rgb is sRGB and cmyk is us web coated.

Should I change my target profile to srgb or will VW change to that automatically. Whats causing the issue in the image? It bugs me because our client says, well our other vendors don't seem to have this issue. Also they're very picky and I'm just trying to get a better understand of the printer and what would cause these things. I want to prevent them for future prints..

Cliffnotes - Grey graidents print blocky. I can see steps, there is a magenta tint in there. printer inks are CMYK LM LC LK M - we have double M, not sure why...?

 

[ColorCrest]

I then informed the 3rd party that I could see banding on their pdf, in my VW rip preview, and in the actual print. I've since received the native file which was done with InDesign.

As a first step and to isolate problems, you might try to build your own version of the gray gradient (alone with no other elements) the best way you know how. Report back with what you find.

 

[Solventinkjet]

One being 19%k The second when I clicked it, showed up as an rgb value. and had 0%k.

This part doesn't quite jive. The RGB color space doesn't have a black channel and white would be 100% of each RGB not 0%K. I'm not sure if that is the problem but it just jumped out at me. I agree with ColorCrest that you should see if a gradient you make as you normally do prints OK or not OK. It will help determine if it's machine/RIP related or file related.

 

[Solventinkjet]

Here is a note from the InDesign gradient help page.

"When you create a gradient using colors of different modes and then print or color separate the gradient, all colors are converted to CMYK process colors. Because of the color mode change, colors may shift. For best results, specify gradients using CMYK colors."

 

[myront]

Not the best way to make a gradient (two shapes) I'm not familiar with InDesign but I know in corel you can make your "fountain fill" then click an icon to "smooth" the transition. And, yeah, not a good idea to mix rgb from one end to cmyk on the other end. And I've always had better luck using pantone shades of gray then export for print as pdf.

 

[jmcnicoll]

pretty common with vector gradients. May have better luck making a gradient in photoshop. FYI designers do a lot of goofy stuff to get what they like on screen and it usually doesn't print well

 

[shoresigns]

designers do a lot of goofy stuff to get what they like on screen and it usually doesn't print well

LMAO you've just written an anthem for the pre-press technicians of the world.

 

[jmcnicoll]

Whats a matter, you can't handle the truth. It's been a constant in all my 30 years of being a graphic arts professional. Was true in the offset world and in the wide format world

 

[bob]

To create a gradient with no visible banding convert the gradient ro a bitmap and add <= 10% noise. The actual percentage depending on your tackle and the gradient with which you're dealing.

 

[Andy_warp]

This happens a lot in gradients where the difference between the two colors is not a big enough contrast.
Adding a schmutz layer in photshop helps. (add 1% monochromatic noise)
Make sure it's monochromatic or you'll get colors in the mix that you don't want.

 

[c.march]

Thank you for all the replies, Its winding down over here to where I can run a backlit test. The only issue is, we don't touch their files. Yet I have to reach out to them and explain the issue. They don't pay me to touch it (too cheap)

 

[c.march]

Just tried to print this with our adhesive back paper profile and it printed way better. just not as saturated.