Forum Feature requests

specifying CMYK colors

somnath
Hi,

I'm using cmyk declarations for colors in my CSS. For the color black, I specify:
color: cmyk(0%,0%,0%,100%)


But when I do "Separation Preview" in Adobe Acrobat, the color values shown is cmyk(69%,67%,74%,64%) and not cmyk(0%,0%,0%,100%). May be I'm incorrect, but the color values shown should be the same.
Note: Separation Preview is a feature in Adobe Acrobat.

Is the behavior correct? Or, Is the CSS statement correct?

Any clarification would be great....


Thanks,
Somnath
mikeday
The CSS looks fine, and I assume that it does actually look black when viewed in Acrobat or printed?
somnath
Hi Mike,

It does "look" black in Acrobat and when Printed.

I wanted to check the color values in the created PDF. So I did a "Separation Preview" from the "Advanced" menu (in Adobe Acrobat Professional 6). This showed the difference in color values. The value specified in css "cmyk(0%,0%,0%,100%)" appeared as cmyk(69%,67%,74%,64%).

I hope this does not confuse things much :-)


Regards,
Somnath
mikeday
I'm using Adobe Acrobat Professional 7, but can't find a "Separation Preview" option under the "Advanced" menu. There is an "Overprint Preview" toggle, which doesn't seem to do anything that I can see, and an "Output Preview" dialog box, but that doesn't show me any actual color values. There is also the "Preflight" dialog box, but that only seems to list the color spaces and does not give access to actual color values. Basically, I'm stumped. :D
rsands
I also get this problem - old old post I know but i specify true black cmyk(0,0,0,1) and it outputs to 300% black ink mix as you experienced
mikeday
Is there any difference with RGB black, #000?

Whereabouts is this Separation Preview located? I'm still stumped. :)
rsands
Got it done by removing other colour to before the cmyk(). The seperations preview is part of adobe acrobat (not adobe reader). Its great for checking output intents, colours, etc.

adobe.com/acrobat
mikeday
Thanks, looks like I will need to upgrade, as I couldn't find it in Acrobat 7. How exactly did you fix the color, by editing the CSS, or editing the PDF?
rsands
I ended up with just cmyk(0,0,0,0.8) and all was fine after i tried it again
mikeday
Okay great.
rsands
I think it is there in Acrobat 7 also - You need to click Tools - then edit icon and select "Print production". Then go to print production menu tab and output preview is there. its not shown by default i dont think