Underbase, Etc.

[GaryG]

We have been using a 3pt choke on underbases in Photoshop 300dpi files for years.

Now want to do Illustrator choke/spread with .80 choke on UB.

How does one keep from having to choke UB, print film - Unchoke, print Top color film?
Is there a way to have "both" UB and Top color saved to go back to? And not in different files?

Thanks Much,

[jvanick]

Our method:

(we use a custom template for our i-image that already has a 'underbase grey' spot color)

- Place art on the i-Image template, size to final size and place where desired. 
- Add a new Layer underneath your art or use Layer 3 in the i-Image template. 
- Select all.  Copy.
- Lock the Art Layer.
- Place art on the new layer using Command+F (crtl+F for PC) or the Edit/Place in Front function. 
- Hide the Art Layer.
- Delete all black from the new underbase layer (or any colors you don’t want to underbase.)
- Change all colors needing underbase to the Underbase Grey swatch in the color picker.
- Select All.
- Stroke in Black to 0.7 pt. 
- Expand all (stroke and fill).
- Use the Pathfinder to merge everything.
- Select the black stroke using the magic wand tool and delete it. 
- Lock the Underbase layer, show and unlock the art layer.
- Select All.
- Window/Attributes, click the overprint fill until it is checked (not empty or a dash),
- Zoom in, you should be able to see the underbase layer mixed with the art colors, creating a haze. 
- Save the screen file.
- Create the .ps file from the print menu 

[Ryan]

We have always made under base and placed behind art then set artwork to
Overprint fill

Sent from my QTAQZ3 using Tapatalk

[3Deep]

When do what I'm suppose to do, I will make my under base a layer and if a top white is needed a layer also by itself in full color so I can go back and pick which color I need to solid underbase or halftone base.  this way I can go back and change stuff around if needed a  little pain in the butt, but let's face if your doing your art correct and not to have problems on press nothing is going to be that easy.

[blue moon]

choke or trap will be related to the opacity of your inks. If printing with process inks or systems designed to be less opaque, trap will be the way to go.

pierre