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This section was extracted in part from several publications including Liquid Color Software and ColorVision Spyder2PRO Studio 2.0 documentation which are recommended calibrating tools for the system.




Color is something that happens in our brain. Wavelengths of light are interpreted by biological mechanisms in the human eye and brain and translate it to a color. This translation depends of ambient light, the amount of alcohol or caffeine in our body, our mood and many others factors.

In different elements that display the same picture we see variations of the colors that are displayed. For example a desktop CTR monitor does not display the same colors as a laptop monitor.

The Gemewizard is a suggested solution for communicating gem color between users, in order to be as homogenous as possible, all users should have their monitors calibrated, until such calibration will be performed automatically in the future.

Recognizing the need for a simpler method of communicating color information between devices, Hewlett-Packard and Microsoft proposed a new standard default color space for the Internet in 1996. The result, called RGB, is a standard method of specifying color numerically in terms of varying amounts of the primary colors, red, green and blue.

Using this method (RGB) special software system was created to verify the exact position of the color in color space.

Using a US patent-pending program, each gemstone image was digitally recreated in 15 different cutting styles (or color rulers), making a total database of some 150,000 images.

CRTs monitors were almost totally dominant in 1999, but in 2004, LCD monitors account for more than 50% of new monitor sales. This means it is necessary to understand how RGB applies to an LCD monitor, to obtain the best colors results for the Gemewizard.

In order to do so, it is first necessary to introduce the concept of gamma.

Every computer monitor of any kind has a non-linear input-to-intensity response curve. As you send the monitor an increasing level of input (for example, tell it to go steadily from black to white), the measurable brightness increases slowly at first and then accelerates. Gamma is a numerical value that describes how quickly the increase in brightness occurs. An optimally calibrated CRT in its native state (for example, the CRT in the RGB specification) has a consistent gamma of 2.2. (An imaginary monitor with a perfect linearity input-to-intensity response curve would have a gamma of 1.0.) In the process of developing the RGB standard, Hewlett-Packard provided studies and computations to prove that gamma 2.2 is very close to what humans see as a uniform lightness scale for display viewing conditions. In other words, with a gamma of 2.2, a CRT monitor seems to go uniformly from zero brightness (black) to full brightness (white) even though it is not really . Gamma 2.2 closely matches the human visual system.

LCD monitors have a gamma closer to 3.0. The result is that an uncalibrated LCDs image is too dark in the shadows and too light in the highlights, with some color tints showing in the gray tones. Not a good match for RGB, and will display inaccurate color.




Methods for calibration your LCD monitor:




There are three fundamental methods that can be used to calibrate a monitor, as follows:



1. Visual calibration

2. ICC profile-based calibration

3. Mechanical calibration




Visual calibration




It is a sophisticated but purely visual method of calibration.

Liquid Color Sofware falls into this category.

Because it is visual, it is subjective but that is not necessarily bad. Visual does not equate to inaccurate. Liquid Color Sofware takes advantage of the most accurate calibration instrument known; the human visual system. The human visual system is a very sensitive gray-scale detector. It is able to detect very small variations in color between adjacent gray areas. This fact is used to great advantage in Liquid Color is (patent-pending) calibration method.

Liquid Color is a tool to help you calibrate your LCD monitor so that its RGB response curve closely matches the gamma 2.2 curve.

Once an LCD monitor is calibrated with Liquid Color, it becomes an RGB-compliant device, ready to participate as a full-fledged member of the Windows world.


ICC profile-based calibration


In 1993, Apple and seven other vendors founded the

International Color Consortium (ICC) to try to solve the problem of delivering consistent color across applications, operating systems and devices. Today the ICC includes 70 manufacturers and software developers. The ICC's approach to the problem uses profiles. An ICC profile is a data file that describes the color behavior of an input, display, or output device. The data in the file is referenced to a device-independent color model, that is, a mathematical representation of human color response . By always using two profiles, one for the from device and one for the to device, software should be able to convert color data from one device so that it looks the same on another device.

The problems with the ICC profile approach are that it is complex and it does not provide a complete solution for all situations. A given device can have many different profiles, depending on the environment in which it is used. For example, a color printer typically has a different profile for each different kind of paper it supports. The result is that outside of the professional environment (graphic design, pre-press, CAD, animation, etc.), ICC profiles are rarely used.

This method is not significantly better than visual calibration for the non-professional user, in fact, it is probably worse because (a) it is complex, as already noted, and (b) the visual result of any given profile may not be pleasing to the user.

Mechanical calibration



Is the only serious alternative for the non-professional user. It consists of using a colorimeter (an electronic instrument that measures on-screen colors) with appropriate software. The colorimeter is often called a puck because it looks vaguely like a hockey puck attached to a monitor screen with suction cups. Typical prices range from $119 to $999, depending on the model.

Once a colorimeter has measured a series of colors on the monitor, it compares them with a device-independent standard from CIE. The software then makes adjustments to the video card , resulting in a gamma of 2.2.

We recommend for this method:

Spyder2PRO Studio 2.0Complete calibration system for virtually all display and presentation methods

The ColorVision Spyder2PRO Studio 2.0 now provides the digital professional with the ultimate tool for color consistency through virtually all display and presentation methods. Along with the traditional CRT, LCD and notebook calibration capabilities the new Spyder2PPRO Studio 2.0 calibration software also color corrects your multimedia front projector with the same precision, ease-of-use and affordability you have come to expect from the color experts at ColorVision.



Gemewizards is doing all the efforts to offer to you the optimal solution for calibrating your monitor. We are exploring all the software available to integrate it with distribution of the Gemewizard.

We are also making contacts with LCD monitors manufacturers for obtaining a perfect monitor that automatically autocalibrates according to the ambient light and will be optimal for the Gemewizard communications colors system.

Our goal in Gemewizard is that all the users will see exactly the same colors in the monitors and we are working on it.