Profiling multiple monitors

[mpotran]

When profiling - making ICC profiles for multiple monitors, do you prefer running the calibration with the spectrophotometer on a notebook and successively connecting other monitors to the notebook one at a time, or do you install the calibration software on each of the computers and connect the spectrophotometer to each of the computers one at a time.
I am interested which one of these is less hassle?
I profiled my monitors all from a notebook, but with some monitors the dual view mode on the notebook was not perfect - the maximum number of colors on the secondary monitor was 256, resolution 800x600 etc. It all seems to come in place if you install the secondary monitor drivers on the notebook, but i was just wondering what is your usual practice?

[ddbray]

I'm not an expert but it is my understanding the the graphic card plays a major role in monitor calibration. So to answer your question you need to install the calibration software on all computers and calibrate each with the monitor that will be used with that computer.

[Lammy]

That was my understanding as well. But then I read that he had already done it once all from the laptop so I figured all that really matters is that the right profile gets put on the right machine. I'm of course assuming he's using the OS to apply the profile to the display?

All the software does is read the patches displayed on the screen and write the profile correct? or does it do a contrast and brightness adjustment through software?

I've always loaded it on every machine so I never really thought about it before.

[ddbray]

The few monitor calibration softwares tht i have worked with the first step is to set your contrast and brightness then you launch the software that displays the different colors that are read by the spetrophotometer. I'm pretty sure that the video card wil determine the actual color that is displayed and that two different video cards will display the same color differently. There fore in order to properly calibrate your monitors you have to have them hooked up to the computer they will be used with.

[mpotran]

Thanks for the answers. I got the same explanation from X-Rite. So i'll stick to profiling on individual computers.
But... just in theory:
You hook up a spectrophotometer on a laptop, you hook up another monitor too; start the profiling software; the profiling software sends out color signals - color patches to the monitor, the patches are read by the spectrophotometer, then the laptop calculates the profile, after that you copy the profile to the desktop on which the monitor will be used.
I have made one profile this way, and then made an icc profile for the monitor on the same computer thet it will be used on. I ran a Monitor validator (Greteg Macbeth or X-rite) software on the desktop using both profiles to compare the two. First you choose a profile and then, the monitor validator outputs some patches on the monitor which you read with a spectrophotometer. The results were an average dE of 1.37 for the laptop generated profile, and 1.1 dE for the desktop generated profile. Altough there is a difference in the dE between the two profiles, you have to admit that the difference is very small.
So i'll stick to profiling individualy for every computer, but this does get you thinking, right?