Accurate color matching?

[goodnightsweetprints]

Forgive me for the ridiculous question but I never went to art school and I slept through my physics of light class... I have been running a print shop for about 6 months, doing gig posters and art prints for local folks, as well as some CD covers, business cards, etc... I have recently been commissioned to print a set of 18x24s that will be cut into over 7000 4x6 art prints.

I have a nice film printer, exposure unit, big supply of screens, great manual press, and my process for pre-press and printing is solid. My tools and skills are incredibly legit and the end product shows it. However, this commission is going to be a bit tricky for me as it is very important that my the colors and overlay are done exactly to the artist's request (whereas I have been eyeballing it up to now).

I have been mixing acrylics with Speedball and don't really want to jump into house paint quite yet. Short of buying a $600 mixing kit, is there some way of at least getting me close to the right mix? Mix different quantities of CMY inks or RGB inks?

Thanks!

[B-DROID]

RGB inks? Ooof.

Get yourself a Pantone formula guide, that'll at least get you going in the right direction. You'll be able to check out how the colors are formulated and hopefully not turn anything brown.

[goodnightsweetprints]

I know, I know. I was joking about the RGB part but it seems like lots of folks will max based on primary colors (RYB I guess)... Will I get halfway close if I mix according to the CMY values that Pantone gives?

[squeegeethree]

I probably will not get the results you need from CMYK inks alone. You need to have a warm red (mag is cool) and a warm yellow in your mix as well. I find it's also nice to have ultramarine, rubine red, and florescent concentrates in the mix as well.

[goodnightsweetprints]

Thanks, fellas, for your help. I was hoping for something a little less trial and error. I guess I can add paint mixing to my list of specialties.

[kylewbaker]

Nailing spot colors (on white surface) is a matter of patience and trial. Try to do that with as few primary inks as possible -- it's a little trickier with Speedball, as I understand it, because many of their inks have multiple pigments... Search the boards for 'Crosshair' 'mixing ink' and 'Speedball', he's posted some good info on the subject.

I think the big challenge here is the overlapping colors. The straight up spot colors are doable, one way or another, but if the artist's expectations for the overlays are unrealistic you're boned. For that reason it's probably best to hold off on transparency base until you've mixed your colors and are ready to tweak accordingly for them overprints.

[weathermaker]

Mixing is harder with Speedball because there is a strong opaque base, aka each color has white in it, so when trying to make simple colors, you can get off track easily because of the white content, its muddies everything up. TW is the ink to use for color specific work if you don't have a lot of mixing experience with Speedball, it has a transparent base so it won't screw up your colors, and, when transparent medium is added its pretty damn nice. TW uses Matsui pigments for their inks. If you are on a budget for this project, get the Matsui product, and a base you like printing with. Make your colors. Cheaper and total control.

[squeegeethree]

I think TW get's their pigment from a variety of sources. They are not pigment manufacturers that is for sure. The main Matsui line of color is not that diverse. If you would like maximum color diversity I would recommend Daler Rowney System Two screen base with 88 colors to choose from to add to it.

[Fools Gold]

I just bought a bunch of Nazdar 2700 inks . . . they are pretty fricken great; ran about 150 sheets at 90% ink coverage and paper flattened right out. Speedball is full of chalk, that's why it scuffs and has that wierd rough texture and feels like printing sand.

[goodnightsweetprints]

I've had nearly a bottle of decent wine tonight (ran out of beer yesterday) and am feeling frisky. What are the 4 or 5 basic colors I need from TW and where do I buy it from? Excuse me... from where do I buy it?