Request for assistance with calibration of HP LP2475W

[attila.ataner]

Dear All,

I would greatly appreciate some guidance from anyone having experience with calibrating the HP LP2475W:


1) Is it possible for it to be recognized as DDC enabled, so that the calibration software will directly control/modify the luminosity and RGB settings, without need for a pre-calibration?

I use BasICColor and Spyder 2 (though will be getting the DTP-94 puck soon). Before that, I was using ColorEyes, but it caused many headaches with my other (Eizo) monitor so I don't use it anymore. Still, neither of the programs recognize the HP monitor as DDC enabled. Just wondering if there is a way to change that.

2) My HP sits right next to my Eizo CE240W. I calibrate them both to identical settings and they end up matching quite closely, but not exactly. The HP is always slightly warmer (in overall tone) than the Eizo.

Is there a way to change this, i.e., to have them match (more or less) perfectly?

3) Lastly, if a slight but discernible difference between the HP and Eizo is just inevitable, which should I trust for color correction work in Photoshop or Lightroom? Apart from the obvious - namely, simply doing many prints and comparing - is there any way to determine which monitor will match final output prints more closely? (This might be a silly question, I realize.)

Many thanks in advance for any guidance/advice!

Cheers!

Attila

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www.attila-ataner.com

[GerardK]

Hi Attila, I have a HP lp2475w, I hope I can be of some help.

As to 1), I don't quite see what you mean. You can enable DDC through the on-screen menu, press Menu, Management, DDC/CI Support, press On, but that's the default so it should be On already. But still, I calibrate with Eye-One Display 2, it doesn't quite work like that. You set the values for Brightness, Contrast and R, G, B values through the on-screen menu or, much easier, the HP Display Assistant. The Eye-Match software helps you adjust the settings as closely as possible to desired values, then measures the patches the monitor displays, and then builds a profile on what it measures to correct to desired values. The profile doesn't actually adjust the values for Brightness, Contrast and RGB values.

As to 2), I noticed something that others have also noticed (check Dpreview forums) - unfortunately the screen isn't quite uniform, I don't know whether you noticed. Apparently this is not uncommon for screens of this type, but it's a bummer nonetheless. The right side of the screen is slightly but visibly warmer (redder) than the left side of the screen. So I calibrate a 'sweetspot' just left of the centre where I usually check my photos in Photoshop, the right side is where the menu etc. are. However you calibrate, there will always be an area to the left or to the right that won't match your Eizo.

Also, you may have noticed that the factory default settings for the RGB values are set to 255, 255, 255. This is way too much. You can adjust the Brightness down to 20 or so, but I noticed that that gives too much red in the highlights. If you first adjust the values for RGB in the on-screen menu or in HP Display Assistant to more moderate values such as 180, 180, 180 with Brightness to a relatively higher value e.g. 70 or 80, and start your calibration from there, you get a much smoother result.

Hope this helps,

Gerard Kingma
www.kingma.nu

[Czornyj]

Ad 1) No, it is not possible. The profiling software must support hardware calibration to do the trick, and the panel must support the possibility of automatic hardware calibration. Eizo CG/CE hardware calibration is supported by BasICColor display 4 profiler, and it's on the list, but it is a panel that was designed to be hardware calibrated.

Ad 2) Calibrate your HP, measure it and check the chromacity coordinates (x,y). Then in Settings>Color temperature>Other white point enter these coordinates, and calibrate your Eizo

Ad 3) You can't really calibrate two different panels to get perfect match between them. The spectral characteristics of their backlight are different, the colorimetric coordinates of colorants are different, and that's something you can't calibrate - so it's technically impossible. The display is profiled after calibration, so the CMM in color managed application will correct the differencies, but only to a certain extent. In some cases HP can give you better softproofing results, but in most cases Eizo should be superior, becouse it can be calibrated much more precisely.

[attila.ataner]

Thank you both for taking the time to respond - very kind of you!

OK, I get it now I think - basically, I can't do with my HP that which I can with my Eizo - namely, have BasICColor independently deal with the luminance and RGB settings because the HP panel is (likely?) not designed to support hardware calibration.

Just in case, I'll call HP and ask them about this, now that I know the proper terminology (thanks to you guys). I know that HP puts out its own calibration/profiling  hardware & software package ("HP Advanced Profiling Solutions", actually manufactured by X-Rite) so it just might be that the LP2475W does support hardware calibration but is not on the "list" of, or is not supported by, either ColorEyes or BasICColor. (I gather, similarly, the high end NEC monitors have their own profiling/calibrating solution and are not supported by 3rd party software like ColorEyes or BasICColor because NEC, I gather, has not disclosed the requisite information enabling ColorEyes to "communicate" with NEC monitors.)

Anyway, thanks again - this is quuite helpful - and I hope others can gain fromt his info too.

Best,
Attila

[attila.ataner]

PS - GerardK, you mention "unfortunately the screen isn't quite uniform, I don't know whether you noticed" - actually, I have not noticed this and I've looked carefully. My HP is quite uniform - maybe I lucked out and got a better panel. If anything, what I've noticed is a very slight "vignetting"-type effect, where the center is slightly brighter than the outer edges - but I can barely notice it only when the screen is pure/blank white.

Cheers!