Monitor calibration with Parhelia 128R

[mutz]

Don't think it's unethical to post this here too. Maybe you guys know some answers. Here is the exchange I currently have going over on the Matrox tech sup forum:

Me:
With previous G cards, I had no problem "calibrating" both monitors on dual head.

I've had my Parhelia for a year now, and with both ColoReal or Adobe Gamma I've never been to get dual head calibration quite right. Monitor 2 has always been too light and has a red cast.

I've just bought a ColorVision Spyder Pro with OptiCAL to try to get it right and to nail down what the problem is. The problem seems to be the Parhelia because the problem follows port 2, not the monitor.

I've tried all the usual things that might have influence, changing cables, etc., and DDC or BNC doesn't change anything either. I know XP doesn't support dual head, but using PreCAL on both monitors with no profile loaded won't close the gap because port 2 is beyond the range of monitor adjustments.

I'm operating at 1600X1200, 16.7M colors and 85Hz on both monitors in independent mode. I tried stretch mode and if I switch a and b, the problem follows b.

So the question is, do you have some suggestion that I've missed, or is the Parhelia out of spec/defective?

PeterB:
Try this with coloreal
Setup your 2 color profiles, apply and save them, do not reboot.
Go to START, RUN, Type MSCONFIG, Go to the STARTUP tab, Uncheck Coloreal
Now reboot.
You should have the settings you selected previously, still applied.

If still the same fill out online rma request at http://rma.matrox.com/

Me:
Thanks Peter. I did that with ColoReal before, which was how I managed to get by for a while. But that was just an unsatisfactory compromise which looked ok, but the colors and gamma were not professionally correct and that has gotten me in trouble. I am now about to do a book of photographs and I can't afford trying to wing it with guess work.

ColoReal will get you by for the web, but for photo editing, print and press, it doesn't hack it. That's why I must go with a colorimeter. ColorVision has promised a dual head module/update shortly that I would hope will do things right with XP and the Parhelia.

My question here is the card. I read elswhere here that a G card has a LUT for port 1, but not for port 2. Is that the case with the Parhelia?

Is it likely that my card is out of spec/defective on port 2?

It would be a waste of time and money to RMA the card if this is a design factor and not defective hardware. Can you tell me which it is?

[rylan]

Well LUTs should be dynamic for both heads, unless they cheated and only have one for head 0 and not head 1.
Only other thing I can think of is that the video output levels for r/g/b aren't even on the 2nd head.. maybe a incorrect resistor value on the output or a bad dac.

[X-Caliber]

"With previous G cards, I had no problem "calibrating" both monitors on dual head. " How did you manage this? I thought it wasn't possible to calibrate the second monitor.

[Ashley]

I don't know if you can do this with Coloreal (I think not), but each of the three heads has a separate lookup table.

[mutz]

Yes X, the G cards only have a LUT on port one. I put calibrating in quotations because I only meant eyeball matching with software and monitor controls.

Yes Ashley, the Parhelia has a LUT on all three ports, but Coloreal is again an eyeball calibrater and I am using a colorimeter. The biggest problem is Windows which does not support dual head in a color management sense.

I went out and bought a Parhelia 256 (that's what I originally wanted anyway) which refined a few things, and next I'm taking monitor 2 in for a check up.

If ColorVision will now come out with it's dual head calibration module, I'll be getting down to the nitty-gritty.

I appreciate the comments and any tips or ideas are very helpful. There's always something I forgot or didn't think of!

[Ashley]

The problem isn't with Windows per se. You can color calibrate any *independent* display via the Windows or DirectX API.

But if your displays are cloned or spanned, Windows only sees a single "monitor", and it is up to the color calibration software you use to address the LUTDACs directly and discretely. DataColor (who publish ColorVision) could do this if they wanted to, but they chose not to update their direcdac library to support new chips like the Parhelia.

The shortcoming is with your OptiCal software (as well as Coloreal), not the Parhelia...

[mutz]

I'm running in independent mode. What do you mean by "display via the Windows or DirectX API."

I know the Parhelia is fine, just sitting there waiting to be addressed. I talked to ColorVision last week and they are coming with a dual head module now or shortly.

[Ashley]

Since Win98 and DX3 Microsoft has provided a simple mechanism for programmers to pass a modified color lookup table to a display driver - and to multiple discrete display drivers for multi-monitor arrays. Game programmers usually use DirectX, everyone else usually uses the Win GDI call.

If your color calibration software is multi-monitor enabled, you can calibrate each independent monitor separately. It sounds like OptiCal is just now getting round to supporting this.

Unfortunately, this won't help if you pick up a 3rd monitor for your Parhelia, or switch to stretched/spanned mode, since Windows - and OptiCal - won't see this configuration as multiple *independent* monitors.

[mutz]

Thanks Ashely, I just talked to ColorVision this morning and they're working on it. Apparently not easy, but they expect to have it by November, latest end of year. I asked if I could be a beta tester, so we'll see what happens.

I've tried a number of ways to trick XP, Optical and Precal, but this only gives me one really profiled monitor and a better match on the second. In terms of matching, only slightly better than Coloreal.

I'm not a programmer, but do you have any suggestions how I might play with DirectX or Win GDI?

[Ashley]

The programming isn't that difficult, but you'd want to be at least a bit comfortable with programming Windows to begin with.

If I had a colormeter that only worked on the primary monitor, and I needed to calibrate 2 or 3 monitors, what I'd do is this: I'd hook up only one monitor to the primary port so that OptiCal and the colormeter could "see" it, and then I'd calibrate the monitor. Once the calibration was done, I'd save the corrected color lookup table.

Then I'd repeat the procedure for the other 2 monitors, so that in the end I'd have saved 3 uniquely calibrated lookup tables - one for each of the 3 monitors.

Finally I'd hookup all 3 monitors to the Parhelia and apply the saved lookup tables to the appropriate Parhelia DAC.

Its a bit of work and it requires a program that can address all of the Parhelia's DACs independenly, but it does work. If you want me to provide a step-by-step, let me know...

[UtwigMU]

What's with the coloreal thingy that get's bundled, doesn't it enable to calibrate monitors in stretched?

[mutz]

Well, no Utwig. In stretched mode Windows only sees one monitor at 3200X1200 or whatever. In Coloreal in independent mode you can "calibrate" both monitors and then in stretched mode they will probably look ok. But that is only your eyeball calibration which is ok for the web and general use, but if you get down to the nitty-grit of photo/grafic editing and printing or other output you will go nuts. Only using a calibration device clapped on your screen and the appropriate software are you going to start getting WYSIWYG.

Right Ashely, that was what I was on my way to do when I ran into the problem which started this thread (see pic). It turns out to be the monitor which I just took to Sony (looks like I get a new tube under guarantee). The Parhelia 128 was totally innocent, though it was a good occasion to get a 256. Trying to nail down what is what can be very tricky between the monitor controls adjustments and the calibrated profiles when you switch monitor cables, or switch monitor order in software because you have a funky monitor and don't know it. I was wrong to think a pro monitor was above suspect. Yes, I would be very grateful if you would post a step-by-step here, and I am sure a lot of others would benefit from it too.

[Kruzin]

You are mistaken, mutz.
Coloreal does allow independant calibration in triplehead mode, despite the fact that windows only sees one stretched resolution.

[mutz]

I never tried it in triple head, Kruzin, though I have run triple head for a while. The resolution is too low. I've tried quite hard to get the best I could out of Coloreal in dual head, but I found too many flies in the ointment. I never found the monitors quite matched in any mode, though there can be a number of reasons for that. But I'm sure you are right about Coloreal in stretched and I stand corrected.

[WyWyWyWy]

I thought PowerStrip can calibrate individual monitors?

Anyway, Mutz, here are the possible good news:

1. Monitor Spyder

http://www.colorvision.com/store/monitor_geu103.shtml

2. ColorBlind Prove-it

http://www.inkjetmall.com/store/cm/prove-it.html

Both are colorimeter calibration application and support multiple monitors on single PC, although I do not have experience with them.

Mutz, can you recommend any cheap colorimeter (+app) for amateurs like me?

Thanks.