Converting RGB to CMYK

[GregD]

Hey.  I was attempting to use Souldraw.com to print my artwork just because the online reviews are good and the prices are really good.  My problem is that they convert everything to CMYK format and that changes the colors of my artwork.  When I received the proofs back my nice bright greens went to a yellowish-green.  Is there anything I can do to convert them to CMYK myself and retain the original colors?  I tried using an online converter and the images came back just as the proofs did.  Anyone have a suggestion...or should I just use an American printer for 5x the money.  Thanks!

[SavannahLion]

You didn't really say what program you're using to create your art so I tried to find a list of 2D tools that support conversion between RGB and CMYK and this is one that I found.

A fairly decent 2D tools should be able to allow you to separate your color spectrum, and more importantly, tweak those colors to your tastes. Maybe if you told us what tool you're using for your artwork, someone here who is familiar might be able to assist in fine tuning the file?

[Ond]

I can do it for you Greg, It should be fairly easy for me and I'll tweak the conversions to match the original RGB colour profile as closely as possible. It's a good excuse to colour match sideart, marquee and CP anyway.  I should have thought of that, printers prefer CMYK - common problem.

[GregD]

Now I feel like I am taking advantage of you Ond.  If doing this is a royal PITA then please don't worry about it.  Thank you very much....again

[gbeef]

just a heads up Ond.
Soul draw uses CMYK Japan 2001 not SWOP Please keep that in mind. So make sure your color profile is set to the right CMYK profile. ( yes there different kinds and yes and it makes a different) I use this vendor to print some of my work.