Duncan Hothersall wrote:

Sorry for all the messages; I am exploring things I don't really understand. I hope someone can enlighten me!

With the following colour set-up:

\setupcolors[rgb=no,cmyk=yes,spot=yes,state=start] \definecolor[PantoneTwoNineFour][c=1,m=.56,y=0,k=.18] \definecolor[IFSbluetabletint][PantoneTwoNineFour][p=.15]

and then using this tint as a textbackground and also as a backgroundcolor in frames, I am getting complaints from my printers that black overprinted on the tint is 'knocking out' the tint and leaving white on the separated plate.

I have read and re-read the useful msplit.pdf which suggests that the implicit criterium=all will negate this effect, but perhaps I have misunderstood?

Two questions: 1. how can I stop black overprinting from knocking out the tint, and 2. is there a way I can check that it is working properly without sending it to the printer each time?

Thanks as ever for any help. Do I need to post example output?

whow, a demanding color user -) see mag-0006.pdf for more info on properties \setupcolors[state=start,textcolor=cyan,overprint=yes] \setupbackgrounds[page][background=color,backgroundcolor=magenta] \starttext \input tufte \startproperty[knockout]\input tufte\stopproperty \startproperty[overprint]\input tufte\stopproperty \input tufte \stoptext ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com | www.pragma-pod.nl -----------------------------------------------------------------