Plotters Printers Photography CMYK RGB

Use this RCW like a visual aid typewriter key board for color.
See a color and know which color will neutralize it to mix it's shadowed color.

It records correct pigment oppositions for making dark colors with transparent paint or ink. It matches all colors in nature and how they shadow. Use it in Photography, Stage Lighting, Textile Dyeing and color coordinating. The RCW color wheel works, free pigment referenced 5x5 Zip with a CMYK EuroScale Coated profile. Use this profile in either the printer or the image. Not both.

This is how it works with ink artists, 4 color printers and plotters.

A plotter is a larger printer that sprays color as opposed to a printer that picks pigment up from another surface. A plotter is used in printing canvas giclees and is color accurate as any four color press. I have a Roland HiFi FJ52" Plotter.

Here's what I did to this image.

My painting was painted without black pigment. There is this short-fall in CMYK, it starts adding black into the value too early and loses color in the deep darks.

I'm going to make some transparent yellow ink to use in the plotter.

I increased Selective Black in the CMYK Proof Setup's Working Black Plate, and reduced the intensity of the black ink in the plotter with an ink adjustment. Then used the acrylic pigment's transparent opposition colors in thin washes to give the now lighter blacks some color instead of just black. It's amazing how similar it looks to my painting now.

It seems black ink takes over making a pigment that is "painted darker with it's intensity hue only", let's say.. 3 coats of transparent magenta. So instead of having 300% magenta ink in the print, you have 100% magenta ink plus black to make it darker. One could lighten the black ink level and paint in the "darkened by intensity only" magenta colors with a brush.

COLOR THEORY

Printers and plotters use the Computer's RGB color wheel and convert it to the printer's CYMK color wheel. They look almost the same, but not exactly. It's better to change the RGB to CMYK and adjust the CYMK. It's best to convert a RAW image directly into CMYK. Printing any converted RGB profile has some printing problems.

Intensely layered magenta isn't possible because the full depth of the pigments ink won't print with only one coat without effecting the rest of the print, even with the extra Light Magenta ink. CMYK adds black ink at this point.

RGB prints what looks on the computer like a perfectly balanced color wheel, and shifts the cyan and magenta 30 degrees in the print. This expands the Green to Cyan range and shortens the Magenta to Red range. WHAT YOU SAW IS NOT WHAT YOU GOT.. on your printer. Also the printer will not print the higher RGB gamma ranges of color.

The CMYK Real Color Wheel you see on your computer is what you will get on your printer or plotter. It looks much duller in comparison to higher gamma RGB realcolorwheel, but the CMYK is the gamma range that is possible and it is what the printed image will look like. The RGB color system has a much higher color gamut, much of high end color is lost in CMYK.

Give the plotter a CMYK image and profile as opposed to giving the printer an RGB image of higher gamma and letting the printer/plotter convert it. It won't correct the color shift of magenta and cyan, that takes an original CMYK image.

The newer plotters give more to play with, with as far as matching colors to a painting or photo. Longer ranges of colors can come into play. For instance, Cyan and Yellow pigment or ink must cover from cyan to yellow in both CYMK and RGB. That's 130 degrees plus the extra 30 degrees because of the RGB color shift. The colors between Green and Yellow are limited by at least 15 degrees. The new plotters give the option of adding another color to CYMK. An extra pre-made Green to mix with Yellow, that evens out the colors available to be reproduced in the green to yellow range. It's not perfect, but it can help. I didn't like it.

The most useful combination of color in nature painting is green and a yellow/orange/red mixture. Green and Magenta make a neutral black from color, the shadow color of green.
Orange is the other color that is hard for the printer to match because of the 30 degree color shift in RGB and the muddiness made from the opaque yellow and transparent Magenta mixed wet. Orange is the second extra color available to my plotter. Having an extra orange makes a greater range of browns and better green/orange color combinations and evens out my ink usage. It works, but after changing out my colors to orange and green and testing it out I changed back to my light cyan and magenta.

My best reproductions are made with a CYMK image that has been worked on. An RGB image can be converted to CMYK closely in some respects by giving it first a sRGB profile then a ColorMatchRGB.icc profile before changing it into CMYK in the plotter. This will not correct the color shift of magenta and cyan though, that can't be corrected. ColorMatchRGB works as the profile if used in the plotter only also.

As a CMYK image either the plotter or the image needs a profile to print with. One of them should have no profile.

After this point it can be re-converted to RGB again if you wanted a gamma limited RGB. The "color shifted" RGB should now contain the "color shifted" CMYK colors with an sRGB profile.

Here, in the image below are the CYMK RCW colors converted into RGB colors for your monitor. A browser won't view in CMYK. The colors look the same though, The original image was made in CMYK. A conversion change in this direction doesn't effect the CMYK colors and removes the color shift RGB has.
It looks like the laminated RCW color wheel I sell to artists for $10. They have no RGB color shift.

The four large color dots are only extra added colors for this example. They are unconverted RGB colors added to a CMYK image that has been converted to an RGB image and worked on. In these conversions the RGB keeps the same colors that were in the CMYK. Now I can add RGB colors to the existing CMYK colors. Yellow to red RGB colors are accurate but not the rest. They won't print accurately.. but I can add them for monitor viewing.

The CMYK print is the photo below, it and the monitor image both show accurate color. The print, from an RGB camera shooting a CMYK printed image and the monitor match. To do this I first gave the plotter no profile, it uses the profile I made for all images going to the plotter.
Than I made a new monitor profile to view and work in. I have a laptop and the monitors are tough to work with, I had to make my own profile that is a little darker and shows all the deep warm and cool grays.

This tells me I should never print from a normal RGB taken image if I want real quality. I should photograph the image in RAW, convert it to CMYK and print in CMYK.

Saying red (which is made of yellow and magenta), is a the primary color and giving magenta a code like PR:122. That's Pigment Red #122 to the Color Index.

Yes, the Yellow, Cyan, Magenta color wheel is accurate, not the red, yellow, blue colour wheel. Compare them. My color wheel adds to that, giving the ability to mix all opposite colors into a neutral black hue.

This is a big problem today, because all of our State's School Standards are commanded to teaching the Red, Yellow and Blue as primary colors. Very sad.