Datacolor User to User Support Group.

Hi! This is my first post here.

What would be the best way to match the color on two identical  LCD
monitors using a Spyder2Pro? The monitors look close but not quite the
same.

Thank you.

On my PC running XP Pro with i1 Display2, all i had to do is drag the calibration application to the other window, then it ll automatically profile the

--- In colorvision_group@yahoogroups.com, "xun wang" <xun911@...> wrote:
>
> On my PC running XP Pro with i1 Display2, all i had to do is drag the
> calibration application to the other window, then it'll automatically
> profile the targeted LCD instead.
> Try it, maybe spyder behaves similarly...
> 
> xun

Just be careful that the background behind each monitor is the same
(color, ambient light etc.)  I'm reading that the background has a
measurable effect.

So I can profile 2 crt monitors on one dual head video card?  or not?  
and have it all work right?

Randy

CDTobie@... wrote:

>
> In a message dated 3/14/06 2:15:13 PM, ttrostel@... writes:
>
>
>> > On my PC running XP Pro with i1 Display2, all i had to do is drag the
>> > calibration application to the other window, then it'll automatically
>> > profile the targeted LCD instead.
>> > Try it, maybe spyder behaves similarly...
>> >
>
>
>
> Actually, with Spyer2PRO, you get a choice of all the available 
> monitors and projectors to choose from at the beginning of the wizard 
> workflow. No dragging or dropping necessary. But the various factors I 
> listed are the items that need to be considered in tweeking two 
> monitors to the closest possible match. Just pushing the "calibrate" 
> button is great, but controlling the details is what makes for the 
> closest possible multiple monitor matching.
>
> C. David Tobie
> Product Technology Manager
> ColorVision Business Unit
> Datacolor Inc.
> CDTobie@...
> www.colorvision.com
>
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Thanks for the replies.

The monitors are identical Dell LCD monitors connected via DVI to a
dual DVI Nvidia Geforce AGP videocard. I am able to calibrate both,
but they remain somewhat different. They are positioned side by side
against dimly lit white wall, the light is coming from the right side
and is fairly dim most of the day. The light does not directly hit the
monitors. Windows XP Pro SP2.

I wasn't targeting luminance values.

One of the monitors is also connected via VGA to another computer with
a Matrox G400 Max card, but I haven't attempted calibrating it yet.

--- In colorvision_group@yahoogroups.com, randy <rlphoto@...> wrote:
>
> So I can profile 2 crt monitors on one dual head video card?  or not?  
> and have it all work right?
> 
> Randy

It works for me. Colorvision installs a utility in Startup folder that
loads separate profiles for both monitors.

However, even if dual monitors were not directly supported you would
be able to calibrate monitors one at a time and manually assign the
profiles and load LUTs.

Yes that s exactly what I m doing. Supposedly windows doesn t support multiple monitor profiling. But obviously that s been proven wrong. though I would like

Thank you, I'll try that.

Tipically in Windows XP to assign separate profiles on a dualhead card
one would need to download a Color Control Panel Applet from Microsoft
and then set it to load LUTs on startup. However with Spyder2 Pro you
don't even have to do that I believe. At least you don't need to load
LUTs through the applet - colorvisionstartup.exe does it instead.
Since I already have the applet installed I can't tell if colorvision
startup would work correctly without it.

It ll probably work the same without the CCPA. I m not using the CCPA and having two different profile loaded on two LCDs from a single graphic card. ... -- 

--- In colorvision_group@yahoogroups.com, "xun wang" <xun911@...> wrote:
>I meant my Radeon 9800 only has one LUT, 

I believe this statement is incorrect. I think most modern videocards
would support two - although I'm not a technician.

If your calibration software affects only the monitor it's positioned
on that means you can assign separate LUTs.

--- In colorvision_group@yahoogroups.com, CDTobie@... wrote:
>If you can't get Windows to see your 
> dual head video card as two devices... you simply can't use distinct
profiles 
> for both monitors, without buying a second video card.

You can assign appropriate profiles and load appropriate LUTs on
startup, which is all most people would need.... Which part of it
would't work in your opinion? Without colorvisionstartup.exe one would
just use "wincolor.exe /L" and it would work. I mean it does work.

Oh, OK. I was considering getting two videocards for my next system,
but if PCIe works OK I guess one would be enough. I know the applet is
not perfect (and that's why I was considering two cards) but for most
intents and purposes it is useable.

... I think you re right. It turns out that the 9800 pro has one GPA, but has two seperate DACa. So in case if somebody is wondering if your dual head graphic

Thanks for the explanation. Do all PCIe card appear as two separate
devices or it depends on the drivers?

--- In colorvision_group@yahoogroups.com, CDTobie@... wrote:

> Unfortunately this is not exactly true. If you can't get Windows to
see your 
> dual head video card as two devices... you simply can't use distinct
profiles 
> for both monitors, without buying a second video card.
> 

So the card only has one CLUT?

Still, the fact is LUT loader (either colorvision's or microsoft's)
loads appropriately. To test it just create an intentionally distorted
profile - it will load on startup on the monitor it's assigned to. So
having a card that does not appear as two devices should not prevent
me from making two monitors look the same. Photoshop and other
application will see only one profile but I don't care much about it
for now.

Having two identical monitors look the same is not useless even though
Photoshop will only see the profile of only one of them. After initial
calibration they are much closer to eachother - that's a big plus already.

Well, theoretical discussions aside I figured out the solution that
works for me for the time being.

The problem was the white point in my case. For LCD native wp is
recommended and the monitors had different ones. I actually think it
has something to do with Nvidia DVI screwup, not the monitors
themselves, but anyway...

I decided to leave the "better" monitor at native, then measured it's
white point (6375K - you need to start calibration at a white point
other than Native to get to the measurments part) and then set it as a
target for the second monitor. So now they are much closer. The
software warned me that it's not a good idea to use RGB sliders on an
LCD monitor - but hey, it's not a good idea to work on monitors with
different white points either.

Come to think of it for dual monitor calibration it would be nice to
include a standalone "Measure" function in the software, that would
just measure the white point and luminance levels. Would be nice to be
able to save it as a target as well so you can load it for other monitors.

And I don't see why would somebody argue against the strengths of
their own software.  I understand  David Tobie is trying to correctly
represent the capabilities of the software but the thing is a lot of
dual monitor calibration functionality is available in XP for Spyder2
Pro users even on an AGP dualhead card.

A am able to use the Spyder2Pro to calibrate my 2 monitors that are
both attached to an Nvidia AGP video card running under Windows XP.

I have an LCD and a CRT on the same video card, and both monitors look
quite similar with their proper profiles applied.

These are the steps required to do this in Windows with Nvidia cards:

1. Use the Spyder to calibrate each monitor with a meaningful name.
2. Bring up display properties (right mouse on desktop and select
"properties".)
3. Select the "Settings" tab.
4. Click "Advanced" button.
5. Select "Color Management" tab.
6. You will see a list of color profiles associated with the monitor,
probably the profile you created for the primary monitor and some
existing windows or monitor manufacturer's profiles.
7. Click the "Add" button and select the profile you created for the
secondary monitor to add it to the list.  These profiles are now
available to ColorVision's "Profile Chooser" program.
8. The profile that was created for the primary monitor should already
be set as the default - you can highlight it and press the "Select as
Default" button to be sure.

-------------------------------------
9.  When you start the computer, the profile that as been "set as
default" is applied to both monitors, so the secondary monitor has the
wrong profile.
10. Start ColorVision's "Profile Chooser" application.  (Profile
Chooser is automatically installed with the Spyder software on Windows
machines).  A window of it will open on each monitor.
11. At the "Profile Chooser" window on the SECONDARY monitor, select
the correct profile for the secondary monitor.  Now each monitor will
have the correct profile.
12.  Close "Profile Chooser"
13.  Steps 9 to 12 need to be done whenever you restart your computer,
but its easy.

-








--- In colorvision_group@yahoogroups.com, CDTobie@... wrote:
>
> 
> In a message dated 3/14/06 6:34:34 PM, lowlife_inc@... writes:
> 
> 
> > Come to think of it for dual monitor calibration it would be nice to
> > include a standalone "Measure" function in the software, that would
> > just measure the white point and luminance levels. Would be nice to be
> > able to save it as a target as well so you can load it for other
monitors.
> > 
> White point and luminance levels are functions of the calibration,
so you 
> can't just measure them, you need to calibrate to obtain them
(adjusting the 
> whitepoint, for instance, will effect the available white
luminance). Once you 
> have calibrated, these values are available in the info window. They
can also be 
> saved as custom targets, to be, among other uses, loaded on other
computers 
> for matched targeting or used to target other monitors on the same
computer. So 
> I believe everything you are asking for is already available.
> > 
> > And I don't see why would somebody argue against the strengths of
> > their own software.  I understand  David Tobie is trying to correctly
> > represent the capabilities of the software but the thing is a lot of
> > dual monitor calibration functionality is available in XP for Spyder2
> > Pro users even on an AGP dualhead card.
> > 
> Its not our software, these are limitations under Windows XP for any
monitor 
> calibration and profiling product. Its important that Windows users
understand 
> about dual head cards in terms of both dual VLUT capacity, and dual
profile 
> assignment limitations, so that they can choose their configuration 
> appropriately for their uses: if the second monitor if for palettes,
no problem; if they 
> are both for color managed work, then a PCI express dual head card,
or two 
> separate cards of most any type, are probably necessary to get full
color 

> management, and proper matching, with both monitors.
> 
> C. David Tobie
> Product Technology Manager
> ColorVision, Inc.
> CDTobie@...
> www.colorvision.com
>

--- In colorvision_group@yahoogroups.com, CDTobie@... wrote:

>Once you 
> have calibrated, these values are available in the info window. They
can also be 
> saved as custom targets, to be, among other uses, loaded on other
computers 
> for matched targeting or used to target other monitors on the same
computer. So 
> I believe everything you are asking for is already available.

That is excellent. I wouldn't figure it out by myself.

> Its not our software, these are limitations under Windows XP for any
monitor 
> calibration and profiling product. Its important that Windows users
understand 
> about dual head cards in terms of both dual VLUT capacity, and dual
profile 
> assignment limitations, so that they can choose their configuration 
> appropriately for their uses

I know that XP has limitations in that respect. But  for color
matching two monitors loading appropriate LUTs is "good enough". And
your software does it really well. You should play it up instead of
saying that it's not really full color management. It's not, I understand.

Thanks for taking your time discussing this issue. So - is it OK using
RGB sliders for adjusting white point in my situation?

bertha8it's post made me reevaluate my assumptions.

On a dualhead AGP card under Windows XP you do need to use the windows
 control panel color applet loader in the startup folder (wincolor.exe
/L) to avoid manually chosing profiles. It lets you chose correct
profiles on startup without the need for manual correction.

I was wrong stating that colorvisionstartup.exe does the same thing
for an AGP dualhead card. So dual monitor calibration will still work
but it will require a couple more steps configuring the applet. I
believe xun wang has a PCIe card, so he is in a better situation than us.

Good news is that PCIe cards don't not have that problem...

To all -- 

Can someone take the lead to gather the info about this subject, and
summarize it?

I would do it, but I have only one-display systems except for one that is
used only
for tools and other stuff. no color required. (most of you have the same
setup).

If someone can help with compiling this, please let me or John know!!!!  

Thanks!

-kris 

> -----Original Message-----
> From: colorvision_group@yahoogroups.com 
> [mailto:colorvision_group@yahoogroups.com] On Behalf Of lowlife_inc
> Sent: Tuesday, March 14, 2006 11:01 PM
> To: colorvision_group@yahoogroups.com
> Subject: [colorvision_group] Re: Matching dual monitors with 
> Spyder2 Pro - homegrown solution
> 
> bertha8it's post made me reevaluate my assumptions.
> 
> On a dualhead AGP card under Windows XP you do need to use 
> the windows  control panel color applet loader in the startup 
> folder (wincolor.exe
> /L) to avoid manually chosing profiles. It lets you chose 
> correct profiles on startup without the need for manual correction.
> 
> I was wrong stating that colorvisionstartup.exe does the same 
> thing for an AGP dualhead card. So dual monitor calibration 
> will still work but it will require a couple more steps 
> configuring the applet. I believe xun wang has a PCIe card, 
> so he is in a better situation than us.
> 
> Good news is that PCIe cards don't not have that problem...
> 
> 
> 
> 
> 
>  
> Yahoo! Groups Links
> 
> 
> 
>  
> 
> 
>

I use the Win Color Applet to switch between profiles for my computer and 
projector that are both connected to my Radeon 9800 Pro dual-head card, but 
I can only have one profile (and calibration) active at at time, because as 
CDT has said several times, the video card can only take one calibration 
table at a time and applies it to both outputs.

So, AFAIK I can have the projector working with the correct calibration and 
profile, OR the computer monitor working with its own calibration table and 
profile, but with WinXP I cannot have both using a my AGP card and 
photoshop.

Bob frost.

----- Original Message ----- 

From: "lowlife_inc" <lowlife_inc@...>


> bertha8it's post made me reevaluate my assumptions.
>
> On a dualhead AGP card under Windows XP you do need to use the windows
> control panel color applet loader in the startup folder (wincolor.exe
> /L) to avoid manually chosing profiles. It lets you chose correct
> profiles on startup without the need for manual correction.
>
> I was wrong stating that colorvisionstartup.exe does the same thing
> for an AGP dualhead card. So dual monitor calibration will still work
> but it will require a couple more steps configuring the applet. I
> believe xun wang has a PCIe card, so he is in a better situation than us.

--- In colorvision_group@yahoogroups.com, CDTobie@... wrote:

> No, its not. If they are a matched pair, and haven't faded to differing 
> states, then it is a good compromise, but for the cost of a cheap
second videocard, 
> you could have the real thing, and actually profile both. If the two
monitors 
> don't have similar primary color values, then colors simply won't
match...

Are the DACs in the video cards out there pretty much the same?  The
other day I had wondered if there were commercial cards out there
which could run 16 bits per channel instead of 8.  That might be below
the level of perception though.

wow, this thread died quckly...  Was it me?

Lots of opinions, no experts?  

This is the fastest growning group on Yahoo, it seems 
there might be a Windows expert that can help, and a 
member that has the time to document it?  

Oh well....

> -----Original Message-----
> From: colorvision_group@yahoogroups.com 
> [mailto:colorvision_group@yahoogroups.com] On Behalf Of Kris
> Sent: Tuesday, March 14, 2006 11:06 PM
> To: colorvision_group@yahoogroups.com
> Subject: RE: [colorvision_group] Re: Matching dual monitors 
> with Spyder2 Pro - homegrown solution
> 
> To all -- 
> 
> Can someone take the lead to gather the info about this 
> subject, and summarize it?
> 
> I would do it, but I have only one-display systems except for 
> one that is used only for tools and other stuff. no color 
> required. (most of you have the same setup).
> 
> If someone can help with compiling this, please let me or 
> John know!!!!  
> 
> Thanks!
> 
> -kris

--- In colorvision_group@yahoogroups.com, "Kris" <km-yahoo@...> wrote:
>
> wow, this thread died quckly...  Was it me?
> 
> Lots of opinions, no experts?  
> 
> This is the fastest growning group on Yahoo, it seems 
> there might be a Windows expert that can help, and a 
> member that has the time to document it?  
> 

The problem is under the current version of windows you can
*calibrate* both displays on a *single* graphics card with dual heads
but you can't *profile* both of them.  The problem arises because the
current windows OS does not properly enumerate seperate displays.

So ... its ... looks like chicken, smells like chicken, tastes like
chocolate pudding.

Again if you do want to do this on windows aparently the PCI express
dual head card drivers report themselves to Windows as *two seperate
cards* and thats why those particular ones appear to work.

Aparently Microsoft took this one and is providing a solution in Vista
but thats not out yet.

MAC OSX aparently enumerates dual head display cards correctly so this
isn't an issue there.

Tom T

--- In colorvision_group@yahoogroups.com, CDTobie@... wrote:

> High bit cards are common. High bit throughput is not yet available.
So we 
> need to wait for the card manufactures, and the OS developers, to
get it 
> together to allow high bit all the way through...
> 

Printing with 16bit channels certainly helps to keep the banding down
in the saturated colors ... at least when the ink isnt splashing.

OK, that was an extremely informative thread, especially thinks to
David Tobie.

Now, allow me to me rephrase the main question.

"Assuming that the two monitors can be independantly calibrated" what
is the best way to achieve visually matching colors on both monitors
using Spyder2 Pro software? For my purposes the monitors are identical
LCD, but I would like to know a more general answer as well.

Here's my guess: calibrate both monitors and chose the "best". Save
it's settings as a target. Load this target for the second monitor and
recalibrate it. Adjust RGB sliders in the process ignoring the
software warning. You can use this target file for other computers as
well.

I am specifically interested in visually color matching two monitors.

By now I have a very good understanding of XP color issues but please
let's leave it aside. My next computer would be PCIe regardless of the
color management issue. For the time being I'll settle for the best I
can have under the circumstances.

--- In colorvision_group@yahoogroups.com, CDTobie@... wrote:
>
> 
> In a message dated 3/14/06 10:16:39 PM, bernieg@... writes:
>So what you are getting is 
> dual calibration, but not dual profiling. What almost everyone on
Windows is 
> getting is dual calibration, not dual profiling. 

Understood. Now, ignore dual profiling - let us know how to do dual
calibration right.

> when it can be fixed for $50 (spent on a cheap video card)...

For users with any need for 3d performance capability on both monitors
this is not an option.

I don't think I ever claimed that the color applet is a magical
solution. It's just the best thing AGP-based XP users have for now.
It's definitely better than nothing.

Oh, man I'm dumb. You can load an ICC profile from
C:\windows\system32\spool\drivers\color\ as Target - end of story.

OK, sorry for posting 5 times in a raw but I think I figured it out.
I'd like to have some expert input on this as well - most of this
thread was discussing OS ideosincrasies that don't directly affect
color matching (as opposed to properly using profiles in colormanaged
applications).

This assumes you have identical or similar monitors and are trying to
match the colors on them as much as you can:

First you would calibrate both monitors and chose the one you like. 

If the whitepoints seem off on both of them (like, they seem too
yellow or whatever) try recalibrating both to a known whitepoint
(6500K) and see if it looks better to you. At this point your monitors
may look close enough to just leave it at that. However I assume if
you work with LCDs having at least one of them calibrated to Native WP
should have some advantages so in this case you'd keep calibrating.

After calibration you have an option to File/Validate - essentially it
measures the resulting output and compares to the Target output. You
can go ahead and do it and then print it out if you want - it's an
informative printout.

Then chose the monitor you don't like and go and load Target
(File>Open Target). Navigate to where the profile for the first
monitor is stored (in XP C:\windows\system32\spool\drivers\color ...
whatever your first monitor profile is named). Load it as a target and
go through the process - it will include tedious monitor RGB and
Brightness (backlight) controls manipulations.

After it's done your monitors are supposed to look very close. Do the
Validate thing to compare the printouts. If all went well they should
be really close.

Most people would be done at this point. Colorvision loader will load
profiles on startup.

Now the unfortunate Windows XP AGP card users like myself will only
have one profile used by the OS and it will be evident after you
RESTART your system. So what was the point, right? A half-baked
solution is an LUT loader that comes with a freely downloadable
Microsoft Color Control Panel Applet. You would want to install it
before calibration. Then add a shortcut with an /L extention to your
All Users Startup folder
"C:\Program Files\Pro Imaging Powertoys\Microsoft Color Control Panel
Applet for Windows XP\WinColor.exe" /L. And remove the
Colorvisionstartup.exe from there (and Adobe Gamma and whatever else
could attempt to manage color). The loader will only adjust colors on
your respective monitors (/L stands for Load LUTs) without actually
achieving a fully colormanaged worflow (like, Photoshop will only see
one profile).

I wish somebody more professional than myself wrote this.

Hope this helps - feel free to correct me.

It sounds like spyder2pro sure is complicated to calibrate for dual monitor... my calibration on a 9800 Pro AGP card was simple and easy with i1 display 2... 

--- In colorvision_group@yahoogroups.com, "xun wang" <xun911@...> wrote:
>
> It sounds like spyder2pro sure is complicated to calibrate for dual
> monitor...

No. My goal was not calibrating dual monitors - it was color matching
dual monitors.

Like David Tobie has mentioned for calibration in Spyder2 Pro you
don't need to drag anything - just chose the monitor from the dropdown
list.

Speaking of which for calibrating dual LCD monitors to 2.2/Native I
could've used a much cheaper Spyder2Express to calibrate one at a time
and manually assign the profiles.

To clarify - dual monitor calibration is a snap in Spyder2 Pro. You
just use the dropdown menu and the process starts at the appropriate
monitor. No issues there.

My question is matching the colors between the two monitors.

oh, I might ve skipped reading few posts. But still, if you calibrate two identical monitor to the same standard, in a way it -is- matching the two. ... -- ...

What would you consider the same standard?

For LCDs 2.2/Native is a standard I believe. Therefore if Native white
point is different on two monitors then your colors are different.
They are accurately described in the generated profiles that are used
by colormanagement-aware software but they visually look different on
monitors. Then there's black and white luminances that are also different.

And with a colorimeter you can measure it, print it out, compare. You
see the whole thing. 

The idea of matching (AFAIK) is to make two monitors colors look as
close as possible to a colorimeter. Calibration, on the other hand,
tries to match the target values and then creates an accurate
description (ICC profile). In the case of "native" wp there's no
target value to speak of.

--- In colorvision_group@yahoogroups.com, "xun wang" <xun911@...> wrote:

> 2) restart, the loader automatically loads -different profiles- for each
> monitor.

And sorry for repeating it but unlike myself you seem to have a PCIe
videocard that appears as two cards to Windows XP - so you don't have
to jump through hoops like us the AGP misfits.

In a message dated 3/15/06 7:15:40 PM, lowlife_inc@... writes:


> OK, that was an extremely informative thread, especially thinks to
> David Tobie.
> 
Actually, it was a zoo, but there was some good info in there, for those 
willing to wade through. Thats how these groups are...
> 
> Now, allow me to me rephrase the main question.
> 
> "Assuming that the two monitors can be independantly calibrated" 
> 
Only one nit to pick so far: Independently calibrated and independantly 
profiled, or independantly calibrated and jointly profiled? This detail will effect 
the best choice of workflow...

> what
> is the best way to achieve visually matching colors on both monitors
> using Spyder2 Pro software? For my purposes the monitors are identical
> LCD, but I would like to know a more general answer as well.
> 
> Here's my guess: calibrate both monitors and chose the "best".
> 
Think of a motorcycle gang. We think of them as outlaws with no rules, but if 
the goal is for each of them to drive as fast as then can, they won't be a 
gang for long, they'll be spread out over several counties. So they have to 
actually travel at the rate of the slowest, not the fastest, bike. Same with 
monitors. You can't make several   monitors match the "best'; you can only make 
them match the worst. That means the weakest (highest) black luminance target, 
the weakest (lowest) whitepoint, at a whitebalance that the weakest monitor can 
manage. This is why, when I'm told to "match all the monitors in the whole 
office" I have to point out that this would mean the color correction screens 
will be as dull and dim as the secretary's monitor unless we use a bit more 
logical standard. You need to avoid, in most cases, dulling LCDs down to match 
CRTs, or the LCD owners will rebel. You need to check all the monitors, calibrate 
and profile them INDEPENDANTLY once, to see what their specs are, then find 
the group that you are willing to compromise to a single, literal standard.

For two monitors this means to look at the info, see what the native black 
point of each is, and set the weaker as the standard. Look at max white 
luminance, and not set a white target above what either can reach. You may, for a 
range of reasons, set a white luminance target that is lower than the max on 
either. This will give you headroom so that you can continue to calibrate to this 
consistant standard as both monitors fade. And the max may be too bright for 
your ambient lighting and your proofing lighting. I'll post a page from the new 
Ambient Light feature help to the files section for those interested in the 
relationship between whitepoint, white luminance, and ambient lighting.

Once you have an appropriate target both monitors can reach, you calibrate in 
the advanced mode that uses target white and black luminance, as well as the 
same gamma and whitepoint for both, and unless you run into special problems, 
you're done.



>  Save
> it's settings as a target. Load this target for the second monitor and
> recalibrate it. 
> 
Other than using the weaker, not the stronger of the two, and sometime the 
black from one and the white from another, thats the general idea.

> Adjust RGB sliders in the process ignoring the
> software warning. You can use this target file for other computers as
> well.
> 
See issues above, but yes, you can. And yes, you can force the whitepoint for 
a side by side match.
> 
> I am specifically interested in visually color matching two monitors.
> 
Well, the last item would be profiling both and using both profiles, as any 
color variation between the primaries on the two screens will turn around and 
bite you if you can't do this...
> 
> By now I have a very good understanding of XP color issues but please
> let's leave it aside. My next computer would be PCIe regardless of the
> color management issue. For the time being I'll settle for the best I
> can have under the circumstances.
> 
> Within those limitations, I think the above description covers it. Now I have 
to remember to copy that help file to the files section...

C. David Tobie
Product Technology Manager
ColorVision Business Unit
Datacolor Inc.
CDTobie@...
www.colorvision.com

Thank you very much for the instructions. That pretty much answers my
question. The problem of identical monitors connected to the same
videocard displaying different colors has been bothering me for many
years. I'm glad to finally have a (partial) solution.

One more question. I thought about your remark on "independantly
calibrated and jointly profiled". As you know this is the case in my
situation - what workflow differences would that cause?

Thank you. I will fine-tune my workflow and come back with more
meaningfull questions. Overall I am very happy with the results and I
have learned a lot about color management in the process.

lowlife_inc wrote:

>--- In colorvision_group@yahoogroups.com, "xun wang" <xun911@...> wrote:
>
>  
>
>>2) restart, the loader automatically loads -different profiles- for each
>>monitor.
>>    
>>
>
>And sorry for repeating it but unlike myself you seem to have a PCIe
>videocard that appears as two cards to Windows XP - so you don't have
>to jump through hoops like us the AGP misfits.
>
>  
>
So, add a PCI card for the second monitor and stop whining. The damn 
things are cheap. Running two cards has a lot of advantages.  Warning 
though, don't use the same brand of AGP and PCI card.  ;-)  The drivers 
tend to get confused..

-- 
Keith

 
Keith Krebs

"Just some guy," caretaker of the Multiverse's largest EPSON printer 
User Community (highly recommended by Vogon Poets and MegaDodo 
Publications), at:
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and  the Multiverse's largest Canon printer User  Community at:
http://groups.yahoo.com/group/Canon-printers
"For the rest of you out there, the secret is to bang the rocks together 
guys"

 

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At the end of this thread I mentioned that I am completely saticefied
with the color matching achieved on an AGP card. I do not have any
complaints.

For me using a second card is not an option or at least not a cheap
one - I need good Open GL performance on both monitors.