Nec p221w + Spyder 3 different green primary

[taschin]

<p>I have a LCD monitor NEC P221W which I periodically calibrate by Spectraview ii and a colorimeter DATACOLOR Spyder 3 PRO. I noticed that the xy colorimeter coordinates of green primary are different from that reported for the same monitor. I did a quick search around on the web and I found the values reported below. These have been extracted from the summary information windows of Spectraview ii found in the related website. All refer to the P221W.<br>

NEC MDSVSENSOR (Costum iOne Display v2) <strong>x=0.210, y=0.687</strong>, (http://www.shutterbug.com/content/nec-spectraview-ii-color-system-best-system-price)<br>

X-Rite iOne Display v2 <strong>x=0.223, y=0.696</strong>, (http://farm9.staticflickr.com/8028/7353205626_98c4a4a3c2_z.jpg)<br>

NEC MDSVSENSOR (Costum iOne Display v2) <strong>x=0.207, y=0.691</strong>, (http://static.photo.net/attachments/bboard/00W/00W52F-231899584.jpg)<br>

NEC MDSVSENSOR (Costum iOne Display v2) <strong>x=0.206, y= 0.695</strong>, (http://connect.dpreview.com/forums/thread/3111377?post=40080499&image=1)<br>

X-Rite ColorMunki <strong>x=0.201, y=0.686</strong>, (http://www.imagescience.com.au/kb/questions/142/How+To+Calibrate+An+NEC+Monitor+With+SpectraView+II)<br>

X-Rite i1 Display Pro <strong>x=0.208, y= 0.683</strong>, (http://printandweb.pl/kalibracja/P221w_i1%20display%20pro_01b.jpg)<br>

datacolor spyder 3 <strong>x=0.165, y= 0.714</strong> (http://www.photo.net/digital-darkroom-forum/00X6ya)<br>

datacolor spyder 3 <strong>x= 0.169, y=0.682</strong> my monitor <br>

datacolor spyder 3 <strong>x=0.167, y= 0.672</strong> (http://www.fredmiranda.com/forum/topic/829989)<br>

datacolor Spyder 2 <strong>x=0.179 , y=0.634 </strong> (http://zoomnikon.livejournal.com/pics/catalog/497/715)<br>

What it seems is that all the measurements of the green primary performed by the spider 3 are different from those done with different instruments.<br>

Considering that the CororMunki is a spectrometer, I think that the measurements performed by this one are more correct, and that the Spyder 3 get a wrong value for the green primary.<br>

Measuring the Y value of my green primary with Argyll and supposing the same Y value for example for the measurement obtained with the ColorMunki, I calculated after the Lab transform the difference DE2000 which is around 4; is this a large error?.<br>

The Spyder 3 is declared as colorimeter for wide gamut monitors. Isn't it so? Then why this behavior?<br>

What do you think about this?<br>

Thank everybody<br>

Bye Andrea</p>

[custom film holders for fl]

<p>You are comparing measurements of different monitors each calibrated with different measuring devices. Each monitor and each measuring device is going to have some variability (and still be within acceptable specification). With both of these factored in, variability is inevitable. Even if you were able to measure one monitor with two examples of the same model of measuring device, you are probably going to see some variation. Hopefully it would be a very small variation but you would be surprised how large it can be sometimes. Even with a high-end device like an i1 Pro the device can read slightly differently when taking multiple readings from the same chart. That is why good print profiles are often a combination of multiple readings of a target set that combine the data and average out any outlier data.</p>

[taschin]

<p>Dear Doug, I know that the monitors and the measuring devices are different, but I don't think that this difference is due to some variability of the green primary of the LCD or the instrument reading. The variability about you talk, for my opinion, is that visible in the oscillation of the value for example from 0.201 to 0.223. Moreover, more or less the filters used in the LCD of the same model are the same. From the values above, you have to admit that the spyder 3 seems measures a x value of the green primary lower. But you should be right, so I ask to the Spyder 3 and P221W owners what are their green primary xy values, just for curiosity. Thank you. Andrea.</p>

[roger_smith4]

<p>With my P221 I use the factory primaries as my Eye One Display doesn't seem to get close at all on its own. Check "Factory measurements" in Edit>Preferences>ICC Profile>Source</p>

[taschin]

<p>Dear Roger thank you for your answer, it is a pleasure to talk with you. Your tutorial "A guide to improve your Scan Quality" was been very important for me and from this I learned a lot of things, and it allowed me to know Vuescan and the luminosity masks of Tony Kuyper. Thank you again. About the monitor, I'm perplex . You say that I have to choose "Factory measurements", but Spyder 3 should be a colorimeter suitable for wide gamut monitor. By choosing the "Factory measurementsthis" option, the colorimeter is exploited only for the calibration and not for profiling being the profile a matrix type. Moreover after the calibration I usually profile the monitor with Argyll in order to have a LUT profile. So, what you suggest me is to use the factory primaries and then use the factory profile?</p>

[digitaldog]

<p>Roger is correct, you want to use the Factory measurement option in the software but <strong>even then</strong>, expecting different devices to produce the same values isn't going to happen. In a prefect would it would. I've seen the same software with differing instruments provide quite different values. I've seen the same instrument using different software report different values. It isn't at all uncommon to find somewhat older Spectrophotometer and Colorimeters from different companies providing different values. This is one of the reasons why X-rite has tried to get what is called the M specification** of measurement standards (if you will) invoked. I have actually seen differences in the reading of white within the same instrument and company but with different revisions! The Rev C iSis and Rev E Isis from X-rite don't measure white the same (the dE values are nearly 2!). </p>

<p>The numbers do NOT matter. What values you target to produce a visual match from display to print (or whatever you hope to match) is all that counts. If the white balance of product A needs to be CCT 5750K and product B needs a CCT 6200K to match, that's all that counts. </p>

<p>Lastly, the Spyder 3 is far from the ideal colorimeter these days. </p>

<p>**more info about the M specification here:<br>

http://www.luminous-landscape.com/reviews/accessories/eye_one_pro_ii.shtml</p>

[taschin]

<p>Thank you Andrew, I'm sorry for my insistence, finally with spyder 3 what you and Roger suggest is to set the factory setting and use the colorimeter only fro the calibration and then use the factory matrix profile. Isn't it so?<br>

Bye and thank you again for your time.</p>