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While D65 is a quite good "fire an forget" solution for simple setups, deviating from that white point is not so uncommon, especially in the graphic industry. The display white point to choose depends on the actual environment/ color matching conditions. Furthermore the effects of observer...

D50 ist the communication standard for the ICC workflow. The characterization data is recorded under that illumination for reflective measurements (by offsetting the reflection values against its constructed SPD) or chromatically adapted in the emissive case from the actual display white point...

I'm very busy at the moment. Will answer your questions as soon as possible but it may take one day - but already one short hint: If you carefully look at the calibration process you will see that it consists of two parts: The calibration itself (will only display neutral tones) which linearizes...

It doesn't matter. Games are not colormanaged. There will be no transformations from and to a PCS based on participating profiles. Maximum you can achive is to maintain the linearization data contained in the display profiles vcgt (only if you don't have a display that can be...

Looking at the pictures there is no difference between the two samples. The greenish-magenta-shift (may be enhanced in the overclockers.ru image due to different exposure/ aperture settings) is quite typical for an A-TW polarizer. If you would place a "non A-TW" IPS display aside (same...

You could try Argyll (most simply via dispcalgui) to enhance the linearization. The generic W-LED characterization is adequate. Please keep in mind that in your configuration (WLED and WCG-CCFL screen) a calibration based on the same whitepoint target will almost certainly not lead to a visual...

We must analyze the problem further. Apart from the whitepoint itself it seems that the greybalance is not ideal (dark grays are distorted) - although the i1 Display Pro has a very good repsonse in the shadows. Which calibration software have you used? What was the target tone curve ("gamma")...

If the color gamut of a WLED model is sufficient for your workflow there is no further limitation in using such a backlight solution. The visual result of an additive color mixture only depends on the color stimulus of the base colors and not their spectrum (your retina contains only three kinds...

A display ICC profile that was created during a software calibration consists of two parts - a colorimetric description of the actual behaviour of your display and linearization data for the videocard LUT that is loaded during system start. Games don't implement a color management - so it's only...

The CIE XYZ color space isn't perceptual uniform. Even CIELAB doesn't achieve this target despite major improvements: The simple euclidian color distance overvalues color differences in saturated colors compared to neutral colors. In order to attenuate this situation modified formulas were...

As I said: A 8bit (per channel) signal can't provide completely smooth color transistions - even if we presume high bit source material and perceptual gamma correction before bit depth conversion (without dithering). "Tonal breaks" in the way I have introduced it (so it is of course very context...

I think the discussion has reached a deadlock - maybe I can help soothe feelings: At first it is essential to make a clear distinction between banding and tonal breaks. And we must clearly define the workflow and the components involved. However: A 8bit (per channel) signal can't provide...

There must be a dithering stage for bith depth conversion. Linearization via vcgt is visually lossless when using an AMD card in a 8bit per channel output scenario. Sometimes you have to exaggerate a little to explain the principle - but irrespective of the legitimate question about input color...

These screens could and can be bought by anyone - therefore I have problems with the word "finally". A TV screen with extended color space must also be bought and the source characteristic still has to match the intended reproduction characteristic outside an ICC workflow. Apart from that an...

No question of the codec. The color triples transport the information inherently. Of course standards must be established because unlike in the ICC workflow we can't rely on characterized data. But it is - apart from backward compatibility constraints - no problem to transport data relative to...

Windows provides a simple CMM and can load vcgt data to linearize a display. But there is no color management "from above". Color aware software explicitly uses the Windows CMM or an own solution (Adobe: ACE) to carry out color space transformations. To reproduce the background image in...

CLUT profiles have their place in the ICC workflow. Especially for output and device link profiles which have to characterize and determine (i.a. black composition of CMYK) complex and often quite nonlinear processes. Nothing speaks against using them also as display profile but keep in mind...

This option doesn't refer to the vcgt (which is loaded into the videocard LUT) but to the gradation characterization data (TRC) of matrix based profiles. Single Curve means that a neutral input value transformed through the profile will result in a neutral PCS value (and vice versa). This has to...

For a display that's OK - they behave quite linear in most cases. "Thick" LUT profiles are primarily intended for output profiles (print). But even when choosing the curve+matrix based profile the linearisation data ist stored as 1D-LUT in the vcgt portion of the profile. Think of calibration...

The visual system also adapts in this situation ("sensory" means my mentioned "RGB gain control") - the quote contains an other quintessence which I tried to explain when bringing the proofsimulation under D50 normlight into play. There won't be a visual match regarding media whitepoint in this...

The visual system will chromatically adapt to the neutral tone(s) - unlike a camera where the white balance must be defined during RAW development (digital workflow). Though D50 (respectively the colour stimulus - not the "synthetic" spd which comes into play for illumination) can be quite...

Adaption processes (think of a "RGB gain control" of the visual system) still take place (also not contradicted by Fairchild). But you rely solely on arithmetic calculations (via transfering and scaling the tristimulus data in a cone response domain) when determining the corresponding colors*...

As I said the whitepoint is a quite flexible factor - especially when only judging only one source at a time. During profile generation (ICC workflow) visual adaption regarding display white is assmumed and the characterization data is adapted to the reference white of the PCS (D50). However...

A display calibration involves a linearisation and characterization. The linearisation - ensuring the desired whitepoint and gradation respectively a good grey balance - can be accomplished via display or videocard LUT. In the latter case this information is stored in the vcgt of the display...

No. The calibration - regardless of whether via vcgt or display LUT - ensures linearity regarding the calibration parameters. Color space transformations are carried out by color aware software based on all participating and characterising profiles (that's why you still need a display profile...

Output without scaling is possible (pixel accurate representation ).

http://hardforum.com/showthread.php?p=1040697852&highlight=#post1040697852 Can be helpful when measuring samples on paper with optical brighteners. With the i1 Pro 2 you are more flexible because it supports - in contrast to the i1 Pro with and without UV-Cut - different measuring conditions...

As I said, that is completely normal in this scenario due to constraints of colorimetry. NEC even implements a convenience feature (METAMERISM in the advanced OSD) that can attenuate these effects - but this is only helpful when not calibrating the screen by yourself. What you can do: Choose an...

Observer metamersim. The CMFs of normative observers (2 degree CIE for ICC workflows) don't fully replicate your personal sensitivity. To achieve a visual match for neutral tones under your conditions (two screens in parallel operation with different spectra) the calibration target has to be...

I don't understand the "sharpness" you are bringing into the discussion now. While having some problems with the term "Pro calibrator" (at least when having a quick look at different forums in the Anglo-Saxon area), Graeme (who was even invited to speak at fogra symposia her in Germany) is...

Never said that. I'm just pointing out that single usage of the i1 Display Pro doesn't lead to unfeasible reproduction characteristics - even from a professional point of view which I can claim for myself (both as developer and user). Therefore my attempt to give some insight into colorimetric...

I will provide you with meaningful data as soon as possible - based on some probes and reference data - but don't expect worse results than the validation of the DCCS calibrated DELL screen. So nothing to worry. You will be able to work with high accuracy. As I said, the absolute error will be...

Of course - the calibration :-) - but I was referring to an inconsistent measurement.

Adjusting the RGB gains is only one small step in the calibration workflow. Without probe I would just rely on the kelvin presets of the screen and choose a value which is comfortable for you. The linearisation takes place in the videocard LUT (software calibration), is loaded from the vcgt at...

I have seen the stated quote but a remote diagnosis is very difficult. Are there really a different color tints amongst the achromatic colors regarding the actual whitepoint (technically speaking: Strong deviations in the a*b* plane) while using the i1 Display Pro which are absent when using the...

As I said: Even if the absolute error would be higher (which is very unsure) than expressed by the dE ~ 3 regarding white (i1 Pro as reference) in my validation - I guarantee that the measurement will still be consistent and comparable to the provided data.

No on the contrary. It's a good standard solution. Even if there is a higher absolute error - the measurement would still be consistent in itself in this case. I'm not saying that that a pure absolute error is irrelevant (it should lie within a useful range) - but in the total context its...

Yes, but that doesn't change the fact that you can reproduce perfectly under different conditions. In a typical home environment the color matching conditions aren't defined anyway. Just one additional note referring to the bias light: If I would use D65 normlight (instead of my D50 solution)...

No. You don't automatically get a wrong reproduction if deviating from D65 which is used as reference white for many working color spaces like sRGB or AdobeRGB. That's a wide spread misunderstanding. Colorimetry can even adjust to the chromatic adaptation of the eye (some kind of gain control of...

Yes, but that doesn't change interaction and effects. And I have already pointed out that we are using spectroradiometric measurements with prosumer equipment too. Regarding which statement from the quoted text? Generally speaking: Research and development in the area of colorimetry science...