How bad is my monitor?

[ComputerDork]

Greetings. I recently decided to get a bit more serious about photography and in pursuit of color perfection I purchased a spyder 3 elite. The only problem is that I still own a couple of cheapo $200 Asus 24" monitors. (One is actually better than the other as it's the next model up or something.)

Some issues that I'm having that I'm wondering if some sort of parameter tweaking might be able to improve:

• It seems like grays between 1-15% are pretty much indistinguishable on both monitors, as are light grays between 85-99%. Calibration did not appear to fix this. Is there anything I can do with the gamma curve (currently at 2.2) or brightness range in the calibration software that might fix this? Currently my monitors are configured for 120cl/m2 and the ambient light is "moderately low" according to Spider3Elite, so I don't think I'm having ambient light or backlight brightness problems....
• After calibration, one of my monitors is showing a slight magenta tint to grays in the 20-25% range. If I switch to the standard manufacturer profile this seems to go away, so I don't think it's an inherent problem with the monitor unless maybe the monitor is just having issues at a white point of 5800K. (Uncalibrated with the current settings it looks more like 6500K.) This was worse when I calibrated the monitor for 6500K because the magenta tent was present around 75% gray or so. I turned on "iterative gray balance" in spyder and recalibrated to 5800K and I'm assuming one or the other may have helped, but didn't completely fix the issue. I'm tempted to just ignore this as the tint is very slight, but it may cause confusion with things like dark clouds in photos.

After calibration I measured RGB brightness and color temp at the full range of grayscale levels with ColorHCFR and got this:
(IRE 1-10 in increments of 1 is plotted but the rest is in increments of 10.)





This seems pretty bad but it seems like I should be able to do something like set the black point to what is currently 10% or 15% gray. Not sure how to do this....

The other issue is that my monitors seem to be a bit "hot" in the middle of the screen compared to the edges, which I'm assuming that I can't really do anything about, but that's OK for now. (The variation in brightness seems to be from 10-20% depending on the area. This is my slightly older monitor. The slightly newer one is a bit better.)


On a different but slightly related note, I want to set up an inexpensive proofing light with solux bulbs. What color temp should I calibrate my monitor to and what color temp of bulbs should I buy?

Thanks for any help you can offer....

[tony22]

ComputerDork, there are people on this board much smarter than I with respect to all things color, however I may be able to at least ask a few questions.

Which Asus models do you have? The answer may explain some of what you're seeing. Things like side tinting, horizontal gamma shift etc are characteristics of various panel types. If you provide the model numbers we can tell if they are TN, VA (or PVA / CVA), or one of the IPS variants. This may tell us a few things.

Do the monitors have full RGB controls? Some monitors have "expert" modes which provide these capabilities.

I looked at the graphs. Yes, they are not ideal. Not sure what to say without knowing what the full range of controls are on your monitors.

[ComputerDork]

Thanks. They are an Asus VW246H (the one with the worst issues... it's older)  and an Asus VK246H. Specs are here:

http://www.asus.com/Display/LCD_Monitors/VK246H/#specifications
http://www.asus.com/Display/LCD_Monitors/VW246H/#specifications

The stats don't seem to say what sort of LCD technology they use other than TFT. It would appear that these monitors are the same monitor except that the VK has a webcam built into the top. (They both share the same user manual.)

They do have individual RGB sliders that can be set from "0" to "100", but the only actual settings labeled "color temperature" simply say "Warm", "Cool", "Normal", and "sRGB" which apparently (based on manual measurements) mean totally different things to these two different "models".

I only found Spyder3Elite's RGB slider option after my last attempt at calibration so I haven't tried using that feature yet. Really I thought they were calibrated pretty well at this point until I got to looking at http://www.drycreekphoto.com/Learn/Calibration/monitor_sensitivity.html and related pages.

Anyway, basically I took manual measurements of a "255,255,255" white patch under all of the different color temperature settings to figure out what they actually meant, I told the calibration software that I had a color temp control in K, then I just set the monitor to the appropriate setting that was closest while still greater than the target color temp.

These monitors also have some sort of silly "scene modes" (a feature Asus calls "Splended") like "Scenery Mode", "Game Mode", "Night View Mode", etc which, at first glance with some quick testing from ColorHCFR appear to do bizarre things that would probably make things worse. (For example "Scenery Mode" seems to cut back on the blue component dramatically. There also seems to be some sort of "skin tone" selection under color temperature when this Splended stuff is enabled.) Why monitor vendors come up with stuff like this is beyond me. I've always left the things in "Normal" mode which I hope means "Disabled".

Hopefully that answers most of your questions....

Thanks for stepping up to help!

[tony22]

These are both TN panels. Here is a good technical review of the VX which may shed some light on its performance.

http://www.prad.de/en/monitore/review/2009/review-asus-vk246h.html (you may have to hit the "Translate" button)

I could not find an equally detailed review of the VW. I think the only difference between the two is the webcam. They both use the same panel.

It seems these monitors do supply the necessary range of adjustments, but I think you'll find most (if not all) photo enthusiasts and professionals not recommending TN panels for color work. You can do a search here or on hardcop to get a whole host of information about flat panel display technologies and their suitability for color work.

See if the prad review gives you any more info about how to set up the monitor. Pop back for an update.

[ComputerDork]

Thanks for the link. This particular "problem" monitor I have isn't even performing as well as their review measurements so I'm thinking that it's probably time to just scrap this thing. (The thing may just be substandard or worn out.) Given how much I've spent on camera equipment it would make sense to spend a little bit of money on a better monitor and give this to someone who doesn't care about color management.

While a EIZO FlexScan SX2462W would probably be ideal and not so expensive as to be totally outside the realm of possibility, I'm wondering if I can get a lower cost IPS monitor that would be sufficient for decent "prosumer" or semi-pro photo and artwork applications.

This site:

http://www.pchardwarehelp.com/guides/s-ips-lcd-list.php

suggests the NEC LCD2490WUXi2 but it isn't claiming an Adobe RGB-sized gamut and I'm wondering if I can get something similar with a gamut almost that wide for around $800.... Any ideas?

[howardm]

the replacement for the NEC 2490 is the PA241 which can be found for $800 (sorry but cant recall where I saw for that price, most places have it for $899 and you really want the calibration kit)

[tony22]

This site:

http://www.pchardwarehelp.com/guides/s-ips-lcd-list.php

suggests the NEC LCD2490WUXi2 but it isn't claiming an Adobe RGB-sized gamut and I'm wondering if I can get something similar with a gamut almost that wide for around $800.... Any ideas?

The 2490WUXi2 manages 97.8% of Adobe RGB so the coverage is okay. It's a good monitor but as howardm points out the PA241 is the more current model. But it's going for about $950. The 2490WUXi2 can be had for about $750.

[pili]

Double check your display's OSD settings, specially anything that might mess with color temperature and brightness levels, like: movie or game mode, image enhancement, dynamic contrast and such.

I'm sure those are not high quality panels and all TN panels are inherently bad because of the limited gamut, posterization and poor viewing angles. This put, investing on a good IPS model would be a great improvement. But I've never had similar problems calibrating TN panels with my Spyder3 Elite.

Cheers,

[ComputerDork]

Just for the heck of it I'm going to reattempt calibration with this problem monitor tonight using spyder's RGB monitor control option. I think this one monitor is just crap though. It's supposed to have a maximum brightness of 300 cd/m2 or something but it can't seem to make it over 130 or so. The thing must either be partly burned out or it was just defective from the start.... (I've gone though the OSD with a fine-tooth comb so I know I don't have any of these super intelligent image enhancement features enabled.)

[ComputerDork]

After a bit more tinkering, it seems that this slight magenta cast in the 20-25% gray range was somehow being introduced by setting the gray balance correction to "Iterative" (instead of just "On" as is the default.) I calibrated Monitor 1 with Iterative, and Monitor 2 without, then only Monitor 1 demonstrated the problem. After recalibrating Monitor 2 with Iterative, it demonstrated exactly the same issue. (But I have to say, they did both match exactly... bizarre magenta problem and all.)

So I reverted the gray balance thing to default ("On"), enabled the monitor RGB control option in the calibration software, then recalibrated both of the monitors, carefully tinkering with the monitors' RGB settings until the xy values, brightness, and color temp read by the colorimeter were right on target.

This seems to have given me reasonable results. Any slight differences I notice seem to change with viewing angle, and at this point I'm pretty confident that these displays are calibrated about as well as they possibly can be. I'm also pretty sure that there's nothing defective about either monitor and that any issues (like 0-13% gray all appearing as black, viewing angle distortion, etc) are just normal limitations of their technology/design.

I still plan to get a more suitable wide gamut monitor of some sort, but at least now I don't feel nearly as much urgency to do so....

So I guess the main lesson here is that "Iterative" isn't necessarily better than default even if it's theoretically more rigorous. (I tried to find some docs on exactly what the "Iterative" setting does and how it works, but I was unable to do so.) So now I'm just left wondering: Why?