# Printing CMYK



## swilbert (Aug 4, 2007)

Hi. I am getting ready to screenprint a cmyk image onto a white t-shirt. I have done the following things using X3: Taken my image and converted it to cmyk bitmap, changed bitmap into halftones, separated the four colors and laser printed them in black onto my film. I am getting ready to expose the art onto 195 mesh screens and see no problem there as I have been able to get good exposure on them in the past even with the smallest halftone dots. Here's my problem: Looking at the artwork, some of the 4 colors overlap quite a bit where there is a solid image. For instance there is to be a brown area in the print and c,m,and y look like they're right on top of one another. So when I'm getting ready to print this image do I flash between colors or just go wet on wet hoping that it will blend on the shirt? Have I done something wrong with separating the colors? Thanks!


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## darwinchristian (Aug 24, 2007)

swilbert said:


> Here's my problem: Looking at the artwork, some of the 4 colors overlap quite a bit where there is a solid image. For instance there is to be a brown area in the print and c,m,and y look like they're right on top of one another.


Swilbert-

process printing involves many variables that need to be exactly calculated to get a constant. (consistent, perfect print.)

this thread has a bunch of good info: http://www.t-shirtforums.com/screen-printing/t30710.html

i don't know much about it, other than what i have read, but a few things to possibly focus on:

proper screen angles. (may need to test from adobe default levels.)
halftone dot shape at oval, and around 55 lpi on a 305 mesh.
hard squeegie, properly tensioned mesh.
tight registration on press.
print wet on wet and play with your print order.
using spot colors to achieve accents, particularly reds.


eh, i'll quit pretending like i know.

good luck...
d
erek.


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## adawg2252 (Dec 12, 2007)

I pretty much know you're not going to have great results with 195 mesh count. You need 305 and in some cases higher. 

Also, like derek said. Hard squeege is key, but so is EXACTLY tensioned screens that are all the same. You're going to need to have the same pressure on each screen because you need to make sure the ink is evenly distributed, or else you'll have weird looking shirts.

You'll have to play with the angle, but be prepared to eat a few shirts before you figure out the angle and pressure on the screens.

Good luck!


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## flopspop (Oct 16, 2007)

Go wet on wet between colors and unless you're seps are at 35 dpi, you're going to need a higher mesh screen.

BTW, the screen angle of your seps is exteremly important so they don't create moire patterns between each other, but also with the screen mesh. When I do sep, I set ALL colors to 70 degrees. I know it sounds strange, but this is the combination that has worked for me for the past 15 years. Once I figured it out, I kept running with it and it's worked fine every time. Try it if you like, there are many angles that will work, this worked for me.

Don't forget to take into consideration dot gain when creating your seps...


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## swilbert (Aug 4, 2007)

Are my results going to turn out bad because of the amount of ink going through a 195? Beacause I have exposed the screens and they turned out good as far as I can tell.


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## darwinchristian (Aug 24, 2007)

swilbert said:


> Are my results going to turn out bad because of the amount of ink going through a 195? Beacause I have exposed the screens and they turned out good as far as I can tell.


because the mesh has to hold the halftone dot. what lpi are you using?




















as you can see, a 305 mesh has more crosslinks than a 195, thus will hold the edge definition of the smaller halftone dot.

if you are using larger dots, a 195 mesh may be sufficient, but as you get into process printing, smaller dots are required, and so, also a finer mesh.


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## darwinchristian (Aug 24, 2007)

Fred i was merely trying to illustrate that finer mesh will support smaller halftone dots. the illustrations were not meant to represent scale.


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## jayjude (Jan 20, 2008)

wet on wet between colors! is this the only technique in using cmyk?


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## flopspop (Oct 16, 2007)

You can try spot drying between colors if you like, but transparent inks need to "mix" when printed to create secondary colors, etc. so wet on wet usually works best.

Another trick to keep in mind is the order you lay colors down. When working with process printing on apparel, I've found that if your print is coming out too blue, for instance, print the cyan first, then magenta, yellow, blk and that will reduce the appearance of blue in the overall print. In other words, changing the print order of the inks can save you from having to do the seps all over again.


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## swilbert (Aug 4, 2007)

All of this has been really helpful, thanks! I printed the 4 color today with what I had available: close but not exact process colors and 195 mesh. The print turned out surprisingly better than I expected! I have since ordered some 305 and the tru tone colors as to get better results next time. I was next going to ask about the color order. I just went light to dark y,m,c,k. The last reply suggested printing cyan first which makes sense after looking at my print. Any more suggestions on color order? 

Also, some areas looked darker than they should have been but when I lightened my pressure, the print was dull in color but well blended. Any help here? Thanks!


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## swilbert (Aug 4, 2007)

1 more thing: If i am printing 4 color process of a black garment should I underbase every dot with white or just lay a solid pallete of white under the design?


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## flopspop (Oct 16, 2007)

Well, I'm not a screen printer, but I've done many separations for process printing and worked side by side with screen printers to work out the print issues.

From what I've learned, you should keep your pressure as consistent as you can and adjust your seps to change lightness/darkness values. Otherwise you get exactly what happened to you, one thing gets better but something else suffers. Typical print order is from light to dark. What I was saying before is an option if the print is coming out with too much of any given color. It may save you from having to have to run the seps over again. Just something to try before throwing out your screens and starting over if the print doesn't come out right.

Depending on how bright you want your print to look on black will determine whether or not you lay down a solid white base or not. If you want bright, vibrant color, then yes, you should lay down a solid base. If you're going for a darker or distressed look, you can halftone the white base. Halftoning the base gives the shirt a lighter feel and breathes better than if you have a solid base, but again, the colors aren't as bright.


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## tman07 (Nov 14, 2007)

Flopspop -question
If your screen angle is the same for all the screens, wouldn't the dots lay exactly over each other (assuming they are lined up correctly)? That wouldn't be good would it?


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## studog79 (Jul 13, 2006)

That is call moire I believe. Also why did you convert it from X3 to a bitmap? If your colors were CMYK in X3 you caould just print your separations from there.


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## swilbert (Aug 4, 2007)

Yes, it is bitmapped.


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## flopspop (Oct 16, 2007)

Yeah, I know it sounds odd, but it's worked for me EVERY time! Besides, even when the angles are not the same, you still have dots overlapping each other, that's how you get all the various shades and tones. Process inks are transparent for that very reason. If you were to try this with opaque inks, you wouldn't get the same results.

Don't get me wrong, I'm not saying that this is the only combination that works. Just that this is the one that's worked for me. I've been using it for the past 18 years of doing separations and I figure it's time to share the knowledge. It's up to you to try it or not, but trying to figure out screen angles is a PITA...!!!


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## flopspop (Oct 16, 2007)

tman07 said:


> Flopspop -question
> If your screen angle is the same for all the screens, wouldn't the dots lay exactly over each other (assuming they are lined up correctly)? That wouldn't be good would it?


See answer above...


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## swilbert (Aug 4, 2007)

I have now printed 2 different designs using 4 color process and they have both turned out great! However the designs appear a little blurry or dull, not as sharp as I'd like them to be. Is there a problem in the artwork? What are some things I can do to sharpen the image??


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## swilbert (Aug 4, 2007)

Thanks Fred! I can understand what you mean about the square edges and the process black which can seem kind of dull. I will continue experimenting!


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## TeddyRocky (Mar 23, 2007)

Art the union CMYK inks plastisol based? Cured as the same as plastisol I would assume?

And how come people keep saying you need a RIP software to print halftones, but when I separated CMYK, my epson 1280 printed halftones fine.


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## TeddyRocky (Mar 23, 2007)

ImageIt said:


> Yes, it is plastsol and cures like any other plasisol. The CMYK inks can be applies wet on wet.
> 
> 
> 
> ...


Oh, oops I must have been misunderstanding. I can only print halftones by splitting channels and creating bitmap halftones. 

So does FastRip not make you convert your graphics to bitmap? Or is that FastFilms? I've been thinking about buying FastFilms but the price is pretty steep! I am going to take a crack at a 4 color process this week since my heat press paper isn't working too well. 

Does anyone know where I can get Union CMYK inks in quarts online? (I usually buy my inks at Midwest Sign & Supply, but I absolutely hate their customer service, they are very rude). I rather not spend my money there.


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## jace1899 (Oct 20, 2008)

Hi! Do you mean that you set all of the screen angles to 70 degrees or all halftone patterns to 70 degrees?


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## flopspop (Oct 16, 2007)

I was referring to the angle of the halftone pattern when you output your separations (which some call screen angles)...


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## red514 (Jul 21, 2009)

TeddyRocky said:


> Oh, oops I must have been misunderstanding. I can only print halftones by splitting channels and creating bitmap halftones.
> 
> So does FastRip not make you convert your graphics to bitmap? Or is that FastFilms? I've been thinking about buying FastFilms but the price is pretty steep! I am going to take a crack at a 4 color process this week since my heat press paper isn't working too well.
> 
> Does anyone know where I can get Union CMYK inks in quarts online? (I usually buy my inks at Midwest Sign & Supply, but I absolutely hate their customer service, they are very rude). I rather not spend my money there.


the RIP converts the grayscale tones to halftones, same thing you're doing in photoshop using the bitmap method, only a rip uses very high resolution to create the dots (and it does the work for you so you save time).


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## red514 (Jul 21, 2009)

swilbert said:


> I have now printed 2 different designs using 4 color process and they have both turned out great! However the designs appear a little blurry or dull, not as sharp as I'd like them to be. Is there a problem in the artwork? What are some things I can do to sharpen the image??


This could be the original art. What resolution is it at? anything less then 300dpi will start to blurr. lower then 200dpi and a photo image will look out of focus/blurred


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## red514 (Jul 21, 2009)

flopspop said:


> Yeah, I know it sounds odd, but it's worked for me EVERY time! Besides, even when the angles are not the same, you still have dots overlapping each other, that's how you get all the various shades and tones. Process inks are transparent for that very reason. If you were to try this with opaque inks, you wouldn't get the same results.
> 
> Don't get me wrong, I'm not saying that this is the only combination that works. Just that this is the one that's worked for me. I've been using it for the past 18 years of doing separations and I figure it's time to share the knowledge. It's up to you to try it or not, but trying to figure out screen angles is a PITA...!!!


one thing i don't get with using the same angle, is there any issues with ink contamination on large volume runs? like if you print yellow after cyan wet on wet, will the cyan contaminate the yellow in the screen after time? with proper off contact is this not an issue?


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## PositiveDave (Dec 1, 2008)

Setting all the angles the same means that the prints are very sensitve to misregistration. Slight errors mean that different amounts of ink are visible which can lead to moire and colour shifts. Rosettes, formed by 30 degree angles, are less sensitive to moire, are not affected by print order giving more consistent colour and are visually pleasing.
The icc profiles are set up expecting rosettes and give a better colour.
I know lots of people using both methods successfully.


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## red514 (Jul 21, 2009)

jayjude said:


> wet on wet between colors! is this the only technique in using cmyk?


not the only technique but this often gives the best photo realistic results.
i've done some runs where we needed brighter colors and we found that flashing between colors gave us the brightness we needed. however, the dots are a bit more noticeable as they did not meld together.

Playing with the order you print the CMY will change the results, it's often best to plan to swap around screens during setup.


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## micromaui-closed (Mar 9, 2010)

Has anyone run across a good video tutorial that runs through the cmyk process- from file separation to printing design to t-shirt?


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## aldenski (Jan 9, 2008)

Going back to your concern over colors overprinting others, there is an art separation technique called "undercolor removal" where all of the cyan, magenta, and yellow are removed from under the black to make the black dark and crisp. As far as cmy printing on top of each other goes, thats the beauty of cmyk printing - they all combine to make secondary and tertiary colors with just 4 screens.


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