At 8:50 AM +0100 5/12/04, Shangara Singh wrote: >It was 12/5/04 1:16 am, when Steve Upton wrote: > >> A monitor profile will describe which COLOURS are represented by those >> numbers. Do not get fooled into thinking that RGB values = colours. RGB values >> need to be sent to a device and observed by a human before they become >> colours. >> >> for a short, light-hearted description, read my "Color of Toast" essay here: >> <http://www.chromix.com/ColorSmarts/smartNote.cxsa?snid=1005&pid=1.pdg> > >Steve > >A brilliant article if a bit too scientific (I had to read it several times >but I now, at least, understand color theory and the need for color >management).
Thanks, yeah colour management can certainly be "heady" at times. Toast was about the simplest analogy I could come up with. >However, I would like to take issue with the following: To have color you >need 1) light, 2) an object and 3) an observer - for our purposes, a human >observer. Without all these components you do not have color. > >This is an old worn, torn argument often used by color management gurus to >justify their huge fees and it just does not hold water. It's like saying, >when I die, existence comes to an end. Of course it does - for you! For the >rest, it carries on, erm, existing. So, colors exist, even without an >observer. A couple of comments: - I didn't want to start a philosophical discussion in the same vein as "if a tree falls in the forest". But being a scientist at heart (which is not necessarily a departure from philosophy) I tend to take the existential view. So, I view it as someone else posted. Light is full of many wavelengths, objects selectively absorb and reflect wavelengths, people selectively sense wavelengths and colour is how it is assembled in the brain. - the science behind this backs it up. When you take a reading of a colour patch on paper with a spectrophotometer (like the Eye-One Photo for instance), the instrument determines the spectral reflectance of the patch. In software (in-instrument or on your computer), the patch's spectral curve is combined with an illuminant curve (typically D50) and human eye response curves. The result is Lab. A number assigned to a human colour response. So even with philosophical arguments aside, we need an object, an illuminant and an observer. > >BTW, where can I buy your Toast Guide�? I just cannot get my wife to >reproduce the toast the way I like it, and consistently. that may be a calibration problem <g> (either on the part of your toaster or your wife) Regards, Steve ________________________________________________________________________ o Steve Upton CHROMiX www.chromix.com o (hueman) 866.CHROMiX o [EMAIL PROTECTED] 206.985.6837 o ColorGear ColorThink ColorValet ColorSmarts ProfileCentral ________________________________________________________________________ -- =============================================================== GO TO http://www.prodig.org for ~ GUIDELINES ~ un/SUBSCRIBING ~ ITEMS for SALE
