[dave kitson]

I know that there are many threads about this already on the Web. I think that I've read most of them but still have less than a totally clear understanding of the nuances.

I have a two LCD setup. Each LCD is on its own video card to facilitate loading of individual LUTs. One of the LCDs is wide-gamut IPS (HP LP2475W) the other LCD is normal TN.
I have swapped the normal LCD with other normal TN models and for the purposes of this post, could see next to no differences between any of the normal-gamut LCDs.

I have calibrated all the LCDs with a Spyder3 sensor using Basiccolor and Spyder3Elite software, both programs giving essentially identical results. In each case the calibration seemed very successful, getting very close to the target of 6500°C, Gamma 2.2 and Luminance of 110cd/m2, and passing all calibration checks with flying colours.

However, when viewing the same (SRGB) image on both monitors in colour-managed apps such as Lightroom or Photoshop, the wide-gamut LCD shows a very marked red tinge compared to the normal LCDs (which match closely). This isn't the normal oversaturation that you get when not using colour management on wide-gamut displays, but a real colour-cast in a colour-managed workflow.

As part of tests trying to understand what was happening, I created a blank white-filled image in Photoshop, photographed it on both LCDs using auto-WB and then imported the images into ACR. As expected, the image taken from the normal-gamut LCD showed as neutral grey, the 'as shot' colour temperature was interpreted as 6480°C. The image from the LP2475W however, showed as almost pink in ACR, with high red values and low green values. The 'as shot' colour temperature was interpreted as 5100°C.

I played around with the LP2475W RGB sliders (lowered red, increased green) until a photographed image was interpreted as neutral grey by ACR (the interpreted 'as shot' colour temp was now reported as 4850°C). This resulted in a much closer colour correlation between the wide-gamut and normal LCDs, but obviously the whole point of calibration is to remove ambiguity due to setting colour balance by eye.

One thing that I have concluded is that the frequency response of the Spyder3 measurement tool is not appropriate for a wide-gamut LCD.

If anyone has any insights or suggestions for calibrating wide-gamut displays or has experience of successfully calibrating a LP2475W, I would be eternally (well for at least a couple of days) grateful.

dave

[Miguel]

Dave,

It seems like you are doing everything right. I don't think the problem is with the Spyder 3, as I know plenty of peers with an IPS monitor that use it satisfactorily--though a few use the Coloreyes software with the Spyder puck on Macs.

Have you googled the pink cast on that HP monitor problem? I believe it is depressingly common over the past year. I have an older version of that monitor and it's excellent but I was lucky to get a good one.

HP has gone through a terrible time with QA on its prosumer monitors and printers during the past three years. Damn shame as HP used to be highly regarded for their engineering and design.

Could you return it? File a warranty claim?

M

[dave kitson]

Dave,

Have you googled the pink cast on that HP monitor problem? I believe it is depressingly common over the past year. I have an older version of that monitor and it's excellent but I was lucky to get a good one.
.....

Could you return it? File a warranty claim?

M

Miguel

Thanks for the response.
If you refer to the infamous pink cast at the righthand side, my initial LP2475W did suffer from this and HP swapped it for a new one that was OK. The cast that I referred to in my OP is only evident after calibration.

I'll have a look at the coloreyes software.

dave

[artobest]

I have used a Spyder3 Elite to calibrate my wide-gamut NEC Spectraview 2690 and found it unsatisfactory to say the least. In my case, the problem was a pronounced greenish tinge. I don't think the Spyder3 filters are quite up to the task, sadly. I get great results using an i1D2.

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Last edited by artobest; 12-14-2010 at 10:09 AM.

[dave kitson]

........though a few use the Coloreyes software with the Spyder puck on Macs.

I have now tried the coloreyes software (PC version) with the Spyder3 puck and the results are substantially the same.

Datacolor have agreed to replace the puck, so I'll update this thread when I have the replacement.

Thanks for the responses..

dave k

[dave kitson]

I received the replacement puck from Datacolor this morning and have just re-calibrated both the wide-gamut and normal-gamut LCDs. The difference is considerable....

The RGB balance to set colour-temperature on the wide-gamut device is markedly different, the pink cast has completely disappeared and SRGB images now look very close on both displays.

A good result....

dave