Every once in a while our Art Department will send out a quick “Tip” to help our customers.  This one is all about the difference between CMYK art and VECTOR art with illustrations to show how different they come out in standard screen printing.  If you are designing your own T-shirt artwork, this is a great reminder of how important it is to start within a VECTOR framework.  That way we can avoid any surprises when your design doesn’t look like CMYK. 

For those of you that have no idea what I’m talking about, don’t care to know anything more, or are just wanting to procrastinate,  feel free to CLICK HERE to visit one of my favorite “procrastination” sites. 

 

CMYK is also referred to as 4 color or full color process; it prints 4 different color plates (always using the same colors: Cyan, Magenta, Yellow and Black) overlapping each other to achieve the full color spectrum. To print ANY color(s) image the same four inks are used.   

CMYK printing

CMYK vs SPOT color printing

Vector Art uses “Spot colors” which are pre-mixed inks. To print an orange, blue, pink and green image, orange, blue, pink and green pre-mixed inks are used. These ink colors are not printed overlapping each other, the ink is applied only to the corresponding area.

SPOT color printing

Spot color vector image

Types of files that are best printed with the CMYK process are full color photographs, or photographic-looking files. Photographs are raster files composed of a multitude of pixels (dots) of different colors. This type of printing is possible but it is expensive and comes with some size/location limitations.

cmyk raster file

Figure 1: CMYK raster file

Although the original raster file above may seem to have just a few colors e.g. orange shirt, brown horse, green eyes, etc. it in fact has so many colors it would be implausible to print with spot colors because with the spot color process, a different pre-mixed ink is applied for each different color section. This type of file is best if printed using the CMYK 4 color process (or full color process) where the inks are blended together to achieve the full color spectrum.

I’ve zoomed in on the horse’s eye (Figure 2) so that you can see how the CMYK raster file has a multitude of different color pixels, when zoomed out, you see a realistic image. Changing the eye to three spot colors only; green, black and white, will change it from a multi-dimensional looking image to a “flat” looking image (figure 3)

zoomed in raster file

Figure 2: Zoomed into the horse’s eye. This is a raster
image composed of a multitude of different color pixels.

Not all items can be printed using CMYK full color process and that is when we request a spot color vector file. If this is the case, the file can be recreated using a limited amount of spot colors.

vector spot color

Figure 3: File recreated using a
limited amount of spot colors

One advantage of spot colors is that you can select the color you want from a swatch book prior to printing and you can rest assure the printed item will be the same exact color because these are pre-mixed inks using an exact formula.

Some items, locations, and imprint sizes can only be printed with SPOT colors. Check with the Art Department before your file is recreated to ensure appropriate color mode.

Alot of this helpful information was found at http://www.gomez-dieter.com/