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Downloads: Calibration Profiles for your Monitor
LCD default color rendering can range from good (the best are factory pre-calibrated) to utterly awful. Color dominances are frequent and lately there has been the particular trend of more bluish colors except in white which has a reddish tinge.
Vincent Alzieu
Updated: January 15, 2008
Calibration: The principle
Generally, with or without material help it’s very difficult and rare to find a good manual adjustment simply through OSD parameters (the screens menu settings). The ideal, recommended and indispensable solution for pros is calibration. A sensor measures the differences in a series of color patches on the screen and these are then adjusted through the creation of new table (LUT for Look Up Table). To better understand this we should mention that there are actually two tables. One is in the screen which is responsible for the more or less good fidelity with default settings. This one we don’t touch. You would have to update a component or at least have writing access to it, which isn’t our case.

We then look to the other LUT, that of your graphic card’s. This is the one that is changed in calibration and which the sensor recreates to compensate for your monitor’s defects. More concretely, if instead of a desired RVB gray of 128,128,128 the sensor detects that the screen displays a 134,128,128 (and therefore an excessive amount of red), it will then anticipate and ask the graphic card for a 122, 128, 128 via its LUT. It does this with all the color patches it analyzes.

In the case of our LaCie Blue Eye Pro, this involves 18 base colors and their various shades. In other words, it’s a much finer process than a manual adjustment via the OSD.

We carry out this operation for all screens that pass through our lab. Tests are published on Behardware.com and Digitalversus.com and over the last three years this represents around 150 monitors calibrated in this way. Unfortunately, we didn’t keep all of the profiles or the ones we kept weren’t even organized well, so we only offer you some of them.

Better color fidelity a few clicks away

Typically this type of screen is not manually adjustable because by reducing blue to balance out the image you actually add a red dominance in lighter shades.

Calibrating a screen is a two step operation of calibration (optimal adjustment of the peripheral) and the creation of the screen’s profile.  The calibration process (we should get into profiling, but will keep things simple) allows attaining better color fidelity.  The method is almost magic and in a few clicks the sensor automatically remedies your display.  The inconvenience is that it is expensive and, for example, our calibration solution, the LaCie Blue Eye Pro, costs around 350 Euros.

Here we offer you a little taste of this tool’s capabilities and what a difference calibration can make.  If you are into digital photography, in many cases these profiles can significantly improve your display.  However, do not think you have hit the jackpot by just having saved 350 Euros.  Ideally, a screen is calibrated every month, week or even some fanatics will say every day! The performance of the panel and other components changes with time while our profiles were carried out with mostly new computer hardware.  This is to say that there is nothing like your own calibration with your own computer, screen and graphic card.  Here we just give you a taste and in a number of cases the result is excellent.

Results: Before and after

Before calibration, we measure the average difference between the desired color and the one actually displayed by the screen.  Results are given in terms of the average dE 94 determined from 18 colors.

average dE > 3: rendering isn’t perfect and is actually problematic above 5.
average dE < 3: color fidelity can be considered satisfactory.
average dE < 2: excellent and good for touching up photos.
average dE < 1: this is almost perfect and we can safely say that the human eye won’t detect the slight differences.

A standard screen has an average dE between 2 and 7.  Two thirds of these are over 4.


Some examples of the dE of certain LCDs before calibration.

After calibration, all screens are below 1 and all benefit from the new profile!

And it’s these profiles that we provide you with.  In the below pages, we give you a first list of monitors and their associated profiles (Hopefully, yours will be there.)  Download and install it on your computer and see if it’s better with than without.  Finally, if you are so disposed, give us some feedback by email.  Here are the manufacturers in alphabetical order and the profiles for some of their screens:

 We also tested their utility with various configurations and put these results in another article (Are our calibration profiles good for all computers?).  We wanted to know if a profile created on a specific configuration (in this case Windows Vista + an NVIDIA card) was usable in other contexts : XP + ATI, Leopard + NVIDIA, etc. and this was indeed the case.

Note: the profile will only function on screens equipped with the same panels (as ours) and models with identical components.  Unfortunately, sometimes manufacturers change panels without telling you.  In this case the profile will not work and you will have to go back and return to default sRGB settings.

Buy a Lacie Blue Eye for the best price!

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