Out of Web Color Warning?

[GoodPeopleFlags]

What exactly does the "Out of Web Color Warning" mean in Illustrator (CS3)? Right now I have a banner layout and the background is magenta. In CMYK, I did C=0, M=100, Y=0, K=0. Then the little square shows up that has the warning. When I click it, the values change drastically. This also happens when I'm going for a rich black of C=30, M=30, Y=30, K=100.

What does it mean? Do I need to click it? The main reason I need to know is that we still currently outsource our printing so I don't know how it affects the color to click the warning and change the values or leave them alone.

Thanks!

 

[iSign]

I'm not 100% sure, but I think this relates to the fact that although your printer is cmyk, computer monitors (& therefore web design) are RGB. Some colors you can specify in CS3 are not capable of being reproduced correctly on the web, & the warning is more for web design work. In your case, there are also colors your printer will not be able to reproduce, but the out-of-web warning won't be of much use in making those determinations. I would disregard the warning, but learn more about the color limitations of cmyk printing.

Many printers print charts that identify CMYK values under dozens or hundreds of swatches. Ask your printer if he does this & if he can send you one printed on banner & one on vinyl (assuming you outsource both)