ICC profiles and what to expect when using them....

[digitaldog]

I wonder if driving some monitors brighter or dimmer affects their color gamut size as measured by the colorimeter and recorded in the resultant ICC matrix profile.

It certainly shouldn’t.

[AS1]

This is why NEC SpectraView allows one to change the monitor profile on the fly.  You can have one profile for general use and the second for photo work.

Alan,
How do you set this up in NEC SpectraView..(I have the NEC Multisynch 2690wuxi)? In the "Picture Mode" I have my calibration in the "Programmable" mode, then there is an "Adobe 98" mode, and a "Standard" mode..? How do I make a second programmed mode that would have a darker brightness and maybe d50 set up for me when I'm making prints...?
Thank you!
Alan.

[digitaldog]

Using SpectraView software (or Multi Profiler).

[AS1]

Using SpectraView software (or Multi Profiler).

Andrew, I have the spectraView software and am using it. Do you mean that I can save two different calibrations and switch between them using the buttons on the front of the monitor OR would I have to open SpectraView and chose a different calibration target when I want to change..?
Thank you, appreciate your input,
Alan.

[digitaldog]

Yes, switch via SpectraView.

[Chris Kern]

Yes, switch via SpectraView.

Yes, great feature.  You can create as many profiles as you want, correct?  I have ones for different color spaces and contrast ratios, and I'm fairly sure I haven't exhausted the possibilities.

My only complaint is that the change isn't faster.  Given a fast channel between the host computer and the display, I would have expected the switch to be almost instantaneous.

[MabeHall]

An ICC profile characterizes or describes how a printer lays down colour in response to an instruction to print a certain file value. For example, if the printer lays down a LAB value of 4,-3,-2 for L*, a*, b* respectively when the file value it is trying to replicate is 0, 0, 0 (neutral black), the ICC profile notes this behaviour. [L* is for Luminance and a* b* define colours - if you are not familiar with LAB. Much profiling works in LAB.] The profile contains some tables purposed for printing, soft-proofing and different Rendering Intents. It is descriptive. When you go to print, the colour management system (CMS) in the computer uses that information to send properly adjusted data to the printer, so that the printer is essentially "fooled" into reproducing the intended file values. Because there are billions of colours and a profile is made from anything like 100 to 6000 patches depending on how constructed, there is a lot of interpolation happening, and of course a lot of conversion because the printer ends up printing in CMYK, not LAB and not RGB. So just think of the profile as a dictionary that provides information allowing colour values in the image file to be reproduced correctly when interpolated and converted through the CMS to the printer.

The better the quality of the your ICC profile, the more likely it will help produce the luminance, contrast, colours etc. that you expected by looking at the photo on the display, assuming of course that the display is properly calibrated and profiled as well. For each profile you need to maintain the same printer driver settings (especially Media Type) used for creating the profile, otherwise it will not be accurate.

You can't adjust how the printer prints in its native state, but you can adjust how the display image looks, which in turn induces you to adjust the image in your image editing software. Taking into account that display light is transmitted and the light reflected from a print is - well - reflected, the different character of the illumination alters how you perceive the image, the reflected image normally looking duller and having less contrast than the transmitted one. So before you start, you need to adjust your display, through calibration and profiling, to account for that, otherwise you will be continuously disappointed. The most important calibration settings for your display profile are brightness, gamma (essentially contrast ratio), black point, white point. Especially the correct brightness would vary depending on the surrounding light you are working in. The brighter the environment, the higher the brightness setting can be, and the lower the lower. Working in a reasonably dim room (to avoid distraction), a brightness value somewhere in the range of 90 to 110 should be satisfactory, but you need to test this. If you get the display luminance and contrast right, it will give you correct perception and prediction (under softproofing) of brightness and contrast

Softproofing with paper colour and black ink simulation enabled allows you to see on display quite reliably what will emerge from the printer, provided your display calibration/profiling and printer ICC profiling are good.
[Mark, I have read almost all your reviews of printers and papers and they are very informative.  My question is in reference to you mentioning that your custom profiles are created in a closed loop system which I understand.  But, if you used a 3rd party generated custom profile (from a good source) made specifically for one of your printers (and selected paper of course), how would your expect your subsequent measurements to go compared to your profiles?  /quote]

[Mark D Segal]

Hi Mabe, extracting your question from my material, you asked:

<<............My question is in reference to you mentioning that your custom profiles are created in a closed loop system which I understand.  But, if you used a 3rd party generated custom profile (from a good source) made specifically for one of your printers (and selected paper of course), how would your expect your subsequent measurements to go compared to your profiles? >>

The only thing "closed loop" about my profile creation and profile evaluation is that I use the same instrument for measuring the profiling target as I use for measuring the evaluation target. Otherwise, what I do is standard ICC profile creation from the same hardware/software that almost every one else uses. With the measurement instrument being the same for both tasks, that reduces instrumentation disconnects to variances within the performance of the same instrument (which happens), rather than the larger variances that could be expected between different instruments. Any profile I evaluate that embeds performance differences between another profiling instrument and my i1Pro2 I would expect to achieve a lower accuracy rating in the evaluation for this one reason alone, and not necessarily that the profile is less satisfactory. I would allow for an average dE(76) evaluation difference of  about 2dE or so before starting to be too concerned about a difference of profile quality in respect of accurate colour reproduction as far as this test takes it.