Black (cyan) knockout issue for black backgrounds

[dimitri]

hi,
anyone can help me with this one.
in indesign now, you have a black background with white copy (or any colour), the black background is made out of 60% cyan and 100% black for a deeper black.
so can you now in indesign set the text (and other objects), to knockout the white (or other colours) more in cyan than it does in black?

sorry if it is a bit confusing,

cheers dimitri

[cari]

Hi Dimitri!

Wie Gehtst (Ok, that might be spelt wrong! but it looks good enough to me!)...

The answer to your question is Yes.

Trapping in InDesign works not at so called object level, but at ink-level (i.e. it looks at individual colour plates), so if trapping is enabled and you have different trapping settings for black and "other" set in your trapstyle, indeed the black will be trapped over the cyan. Set different settings for Trap Width in Default and Black.

InDesign trapping also allows for a so called "sliding" trap, based on density interaction of colours. It measures a certain tonal difference in colours and will then apply slightly more or less trapping (hence the term "sliding") depending on the colour densities, and interaction.

These methods of trapping occur regardless of whether you are using in-rip trapping or Adobe's built-in application based trapping options. However, PDFs and EPS files placed in InDesign will NOT be trapped like this when you are using Application built-in trapping.

Cheers,

Cari

[Cory]

Does trapping work in a composite workflow? IIRC Pagemaker would build the traps in a composite workflow which was a nice.

[cari]

Cory, As far as I'm aware it does.

Select In-Rip Separations, then Application-Built-in trapping and you can generate a composite PostScript file that contains "live" trapping information.

To see this, drop the PS file onto Distiller and view the PDF you create with overprint preview on.

Is this what you meant?