Monday, November 23, 2009

How to (theoretically) roll your own colour matching system

The following gives background and advances an untried method for developing a colour matching system. It hasn't been tried yet, but I'm working on it.

The basic facts: Colour matching systems exist to standardize colour across the different parts of pre-press workflow. The dominant player, Pantone, uses ten different inks to create its spot colours. In addition to spot colour, Pantone employs its own augmented version of CMYK: Hexachrome, or CMYKOG. Hexachrome is supposed to be able to replicate more of the Pantone spot colour gamut than traditional CMYK can.

To roll your own spot colour standard, you'll need:
  • a light spectrometer (build, buy or borrow)
  • samples of ink from various manufacturers
  • samples of basic, elemental pigment
  • a precise scale
  • time
  • various types of paper
First, analyse your ink selection. which colours do the various manufacturers have in common, aside from CMYK? Once you've found a range of widely available colours, it's time to break out the spectrometer. Make some consistent colour swatches. That is to say, lay in a supply of a few types of paper. Take one of your available colours (you'll want to make sure you have a sample of that colour as produced by different manufacturers). Applying your ink evenly, create a swatch of that colour for each manufacturer. You should have several different swatches of the same colour, a few for each different brand of ink (more or less, depending on the number of papers you're testing with).

Next, grab your spectrometer. Use it to measure the different inks, comparing readings across brands. If two inks have the same readings on one type of paper, go on to the next type of paper and make sure they still match. If you get an exact match on all types of paper, score! Now see if any of the other inks match the spectrum. From each colour group, you should get data about which brands match each other exactly. Be sure to note the details. In an ideal world, it should be possible to find a grouping of different ink manufacturers who make matching products (although who knows what the success rate will be in reality). If they match across the spectrum of common colours, you've got yourself a palette.

You can use this palette as a jumping off point for your own colour mixing experiments. You'll eventually want to narrow down the number of different inks. Pantone, as mentioned above, uses ten. With a base selection of inks, consistent across several manufacturers, you can create your own custom palette of spot colours.

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Sunday, June 28, 2009

Describing Colour

Bob Coons has put up a very nice synopsis on the basics of colour perception. Very readable, very understandable. Link


Tuesday, May 26, 2009

OCS Research Report V1.0.1

Version 1.0.1 of the OCS Research Report is now available. Download the pdf.

Revisions in v1.0.1:

p1. contributor list
p6. "The reverse of this is, of course, also true."
p6. "(including #0099cc, the colour of the OCS logo)"
p7. "As mentioned above, Pantone provides mixing instructions to print professionals. These instructions provide the direction necessary to create any colour in the Pantone range from a set of base colours (these colours include process yellow, process magenta, process cyan, process black, orange, red, blue, yellow, warm red, rubine red, rhodamine red, purple, violet, reflex blue, process blue and black). These instructions are laid out in a similar fashion to paint mixing ratios."
pp7-8. "despite the existence of other viable palettes such as Focoltone, Trumatech, Munsell (the rights to which are currently owned by X-Rite, Pantone's parent company), Toyo, HKS, RAL and so on."
p9. "(a Canadian chain of book stores)"
p13. "is" between the words "involvement" and "what" in paragraph 3
p15. a space between "students," and "use"
p15. "Usability: Even if they wish to try Open Source alternatives, many designers lack the skills required to do so. They may find programs difficult to install, with technical issues they aren't used to dealing with."

Formatting changed to minimize excess white space at the tops of some pages.

p11. " and the principles behind it" from after "(FLOSS)"

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Friday, April 10, 2009

Research Report: release 1.0

After yesterday's post of the beta version of this report, it's now time to roll out version 1.0. Changes since the last version include a newly added bibliography and table of contents, changes to the inline citation style and new content added to the section on Open Source and designers.

Download version 1.0 as a PDF

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Thursday, April 9, 2009

Research Report on Colour, Open Source and Designers

A taste of the report:

"The purpose of the following research report is to create context for the Open Colour Standard project. To that end, this report discusses issues of colour, commercial and non-commercial colour spaces, the use of colour in industry, the Pantone colour space and the business behind it, Open Source projects, their adoption and the possibility of Open Source design."

Full report, as a PDF

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Thursday, March 5, 2009

Light and Colour

The human eye has four kinds of sensors: rods, which detect black and white; a cone for red; a cone for green; and a cone for blue. Our perception of colour relies on these sensors.

White light is made up of all the colours of the visible light spectrum. This can be seen when a beam of white light is refracted by a prism. Apparently, Newton had a lot to say about this, as he was the first to prove that white light is made of the rest of the visible light spectrum. More on this once I've had a better look at Opticks. Goethe also had a lot to say about the physics of light and colour perception. Again, more once I've read Theory of Colours.


Thursday, January 22, 2009

First notes on colour theory and history

WEEK4: hand in one to two pages (preliminary overview) about colour spaces and colour theory

  • First colour wheel came from Newton who also assigned colours to the notes of the diatonic scale (synesthesia, anyone?).
  • Red Yellow Blue has been the norm/base of colour theory & mixing since 1831 (Birren, 17) and has existed as a theory since 1731 (Birren, 11).
  • Newton was the first to wrap the visible colour spectrum into a circle in order to form a wheel (Birren, 10).
  • The standard colour space used by computer screens is sRGB. RGB is, of course, Red Green Blue as opposed to Red Yellow Blue.
  • Standard colour space for print is CMYK, or Cyan Magenta Yellow Black. If you think about it, that's quite similar to Red Yellow Blue, except with fancier names and with Black added in.
  • In many media, more pigments exist than just CMYK. These pigments are made of animals, vegetables and minerals (Bustanoby, 9).
  • In the contemporary view of colour, there are the three primary colours, secondary colours (made by mixing together two primary colours), tertiary colours (mix a primary with a secondary), as well as tints, tones and shades of all the above colours.
  • Different colour spaces aren't necessarily cross-compatible. Some colours that exist in sRGB don't exist in CMYK.
  • There are also spot colour systems. These include colour spaces like Pantone. In these systems, instead of mixing CMYK to form a given colour, there is a specified, separate pigment.
  • There are, of course, colours in the visible light spectrum which cannot be represented in either sRGB or CMYK.
  • I need to put some stuff in about how we see light. The cones and all that. As well as additive vs. subtractive colour.
  • Questions: Will digital always be the poor cousin to print and other physical manifestations of colour? How can complex physical colours be paired with their hex counterparts for ease of digital to print colour matching?