Ad
Ad
Ad
Pages: [1]   Bottom of Page
Print
Author Topic: Does a Video card influence color on a monitor?  (Read 3367 times)
Adam L
Full Member
***
Offline Offline

Posts: 186


WWW
« on: December 13, 2010, 04:35:06 PM »
ReplyReply

I have a NEC PA241W monitor that I share between two computers.  My home computer is a high end machine 64bit Win7 with a ATI Radeon HD 5700 Series display adaptor.  My work computer is an IBM 32bit WinXP thinkpad laptop, about 2 years old with middle of road nothing special inside gear.  The monitor is manufactured to swap between two computers by clicking a button on the monitor.  My new computer is plugged into a DVI jack and the laptop is plugged into an analog jack via a docking station.

I didn't expect to see any visible difference when viewing the same image on the same website using the exact same monitor.  But I did.  And the difference was very material to my eyes. 

What influenced the differences in image quality? 
Logged

"That's a lot of money to move a few pixels around"
Chris_Brown
Sr. Member
****
Offline Offline

Posts: 793



WWW
« Reply #1 on: December 13, 2010, 05:21:02 PM »
ReplyReply

Did you install the SpectraView software on both computers and create profiles for each 'puter? These NEC monitors are designed to use the internal GPU controller, not the computer's GPU card, when using ICC display profiles. In addition, switching between various profiles is to be done by the SpectraView software, not the system prefs. However, I'm not sure how the monitor uses the on-board profiles when using the analog input.
Logged

~ CB
Adam L
Full Member
***
Offline Offline

Posts: 186


WWW
« Reply #2 on: December 13, 2010, 06:15:52 PM »
ReplyReply

I don't have SpectraView on either computer.   I'm not sure that should matter as I'm viewing with the same monitor, not comparing one with another.
Logged

"That's a lot of money to move a few pixels around"
feppe
Sr. Member
****
Offline Offline

Posts: 2909

Oh this shows up in here!


WWW
« Reply #3 on: December 13, 2010, 07:08:16 PM »
ReplyReply

I have a NEC PA241W monitor that I share between two computers.  My home computer is a high end machine 64bit Win7 with a ATI Radeon HD 5700 Series display adaptor.  My work computer is an IBM 32bit WinXP thinkpad laptop, about 2 years old with middle of road nothing special inside gear.  The monitor is manufactured to swap between two computers by clicking a button on the monitor.  My new computer is plugged into a DVI jack and the laptop is plugged into an analog jack via a docking station.

I didn't expect to see any visible difference when viewing the same image on the same website using the exact same monitor.  But I did.  And the difference was very material to my eyes. 

What influenced the differences in image quality? 

I have anecdotally the same experience: I changed video carts and the image improved quite a bit - even becamer sharper. It has probably something to do with the hardware, but most likely the biggest impact is from the driver.
Logged

digitaldog
Sr. Member
****
Online Online

Posts: 9119



WWW
« Reply #4 on: December 13, 2010, 07:11:44 PM »
ReplyReply

Quote
I didn't expect to see any visible difference when viewing the same image on the same website using the exact same monitor.  But I did.

Well yes the graphic system does play a role. IOW, you can’t take a display from system to system and transport the profile.
Logged

Andrew Rodney
Author “Color Management for Photographers”
http://digitaldog.net/
EduPerez
Sr. Member
****
Offline Offline

Posts: 693


WWW
« Reply #5 on: December 14, 2010, 01:12:33 AM »
ReplyReply

[..]
My new computer is plugged into a DVI jack and the laptop is plugged into an analog jack via a docking station.
[...]

A DVI link is expected to produce far better pictures than an analog VGA link; most probably the difference in image quality comes from here.
Logged

Chris_Brown
Sr. Member
****
Offline Offline

Posts: 793



WWW
« Reply #6 on: December 14, 2010, 08:33:41 AM »
ReplyReply

I don't have SpectraView on either computer.   I'm not sure that should matter as I'm viewing with the same monitor, not comparing one with another.

What profile is the monitor set to?
Logged

~ CB
Johnny_Boy
Full Member
***
Offline Offline

Posts: 133


« Reply #7 on: December 14, 2010, 12:33:19 PM »
ReplyReply

Of course which video card (and OS and video driver) you use make a big difference in the final color you see! If they were were all uniform, then we would not be calibrating anything for color management (assuming the monitors were all uniform as well). You will have to calibrate both computers against that monitor to see the same color. 
Logged
Adam L
Full Member
***
Offline Offline

Posts: 186


WWW
« Reply #8 on: December 14, 2010, 05:06:37 PM »
ReplyReply

So this boils down to me needing to buy a SpectraView.  I had hoped to avoid that cost and was of the impression that this particular monitor has tight color tolerences making the puck more of a luxury than a necessity.   I have the monitor profile set to Adobe RGB and also to adjusts brightness based on the amount of ambient light.  That last feature is usually overpowered by my desk lamp, another problem I need to tackle.    Thanks everyone.   
Logged

"That's a lot of money to move a few pixels around"
Roy
Full Member
***
Offline Offline

Posts: 196


WWW
« Reply #9 on: December 14, 2010, 06:39:12 PM »
ReplyReply

Don't blame the monitor. It is a fine product.

You cannot do what you wish to do using VGA. The VGA signal is analog, not digital, and two VGA signals are never quite the same, and no VGA signal is going to match a DVI connection.

With two DVI connections you should be able to do what you want. DVI is digital. Ones and zeros. If both computers are correctly set up with the NEC Adobe RGB dispaly profile (which requires you to install and use the NEC multiprofiler app on both computers), the images should be identical.

You can do a custom profile using Spectraview and a puck for the VGA-connected computer and perhaps come close, but that profile will be specific to that computer and its VGA graphics card. That is just a fact of life with analog.
Logged

Roy
hjulenissen
Sr. Member
****
Offline Offline

Posts: 1679


« Reply #10 on: December 15, 2010, 02:00:01 AM »
ReplyReply

Of course which video card (and OS and video driver) you use make a big difference in the final color you see! If they were were all uniform, then we would not be calibrating anything for color management (assuming the monitors were all uniform as well). You will have to calibrate both computers against that monitor to see the same color. 
I think that all monitors have different behaviour, and to some degree vary with time.

I dont think that the same can be said for OS and video drivers? Sure, there are quirks with how they load LUT (or delete them) etc, but are you saying that my colors change if I go from Nvidia to ATI graphics?

-h
Logged
Steve Weldon
Sr. Member
****
Offline Offline

Posts: 1460



WWW
« Reply #11 on: December 15, 2010, 05:42:10 AM »
ReplyReply

Maybe someone more familiar with the PA series can correct me if I'm off-base on this.

A different graphics card 'can' affect the signal, but if everything is working correctly and both are of high quality they 'should' not.  The same can be said for VGA vs. DVI vs. DP vs. HDMI connections.   Even if one is analog and the others digital.

The question is what signal is being sent to the monitor by each system.  Is it a bare driver signal, or is it a profile driven/enhanced signal influenced by some controls (brightness/color/contrast/etc/etc/long list) you're not aware of?

And with an internal LUT monitor.. there is certainly a profile involved because Spectraview II creates one and installs it in the system.  I'm just not sure exactly what this profile involves.  I would doubt it contains the LUT tables as those are handled by SVII via the DVI port (at least on my LCD2690uxi2) monitors.. but possibly a control code telling the monitor where the instructions will be coming from?  I wish someone could clear this part up for me.

I would be very surprised if you ensured a bare driver signal, and possibly installed SVII generated profiles in each, if you couldn't get almost exact matches between the machines.. perhaps a slight white point fluctuation.. but something acceptable.
Logged

----------------------------------------------
http://www.BangkokImages.com
Johnny_Boy
Full Member
***
Offline Offline

Posts: 133


« Reply #12 on: December 15, 2010, 05:50:23 AM »
ReplyReply

I think that all monitors have different behaviour, and to some degree vary with time.

I dont think that the same can be said for OS and video drivers? Sure, there are quirks with how they load LUT (or delete them) etc, but are you saying that my colors change if I go from Nvidia to ATI graphics?

-h
Yeah, OS and Drivers by themselves do not vary over time or copy to copy. They are software, so they are (generally) consistent. What I meant to say is that even using the same video card on different machines, if you are using Mac vs. PC vs. Linux, they look different because they use different gamma settings. That is what I meant by OS. Also as we know some video cards (and the driver/OS combination) can support more colors and better gradients than others.

As noted by others however, if it is DVI to DVI connection comparison, you SHOULD see it identical. My past experience of noticing difference came from using multiple machines with different video cards sharing the same monitor using VGA analog connectors via a KVM. In that case, the color was very slightly different from card to card due to the tolerance range. This is probably no longer true on a full digital connections (so ATI and nVidia should display the same assuming using full digital connectors).

BTW, in this case, I wonder if going through the docking station is also making the color difference greater? It is another analog connector that degrades the signal. I wonder if hooking up the cable directly to the laptop would reduce the color difference?
« Last Edit: December 15, 2010, 05:54:30 AM by Johnny_Boy » Logged
Chris_Brown
Sr. Member
****
Offline Offline

Posts: 793



WWW
« Reply #13 on: December 15, 2010, 08:25:10 AM »
ReplyReply

Maybe someone more familiar with the PA series can correct me if I'm off-base on this.

A different graphics card 'can' affect the signal, but if everything is working correctly and both are of high quality they 'should' not.  The same can be said for VGA vs. DVI vs. DP vs. HDMI connections.   Even if one is analog and the others digital.

The question is what signal is being sent to the monitor by each system.  Is it a bare driver signal, or is it a profile driven/enhanced signal influenced by some controls (brightness/color/contrast/etc/etc/long list) you're not aware of?

From the SpectraView manual:

Quote
• ( Mac OS only) Do not use the ColorSync control panel to switch between different display
monitor calibrations by selecting different monitor color profiles. Always use the SpectraView
application to load a previous monitor calibration. This is because all of the necessary color
adjustments, including the Look Up Tables, are stored in the display monitor and these must be set
by SpectraView. The ColorSync profiles generated by SpectraView contain linear Look Up Tables for
the video graphics adapter.

And:

Quote
• Automatic calibration - SpectraView communicates with the display monitors using Display Data Channel - Command Interface (DDC/CI) which is a two-way communications link between the video graphics adapter and display monitor using the normal video signal cable. No extra cables are necessary. All adjustments to the monitor settings are done automatically using this communications link. A USB connection between the host PC and display can also be used on MultiSync PA Series models only. It is not necessary to manually configure the monitor as all of the necessary settings are made by the software.
Logged

~ CB
Steve Weldon
Sr. Member
****
Offline Offline

Posts: 1460



WWW
« Reply #14 on: December 15, 2010, 09:32:01 AM »
ReplyReply

Thank you.

So the Mac isn't using a SVII created profile, but SVII is providing data via the DDC?  SVII is communicating this data directly with the monitor.  Sounds like the smart way.  Is SVII, Mac Version, storing the information gained during calibration within itself and this is part of the DDC upload?

What about with Win7?  I notice the color manager uses SVII created profiles and they are being loaded?  What's in them..
Logged

----------------------------------------------
http://www.BangkokImages.com
Pages: [1]   Top of Page
Print
Jump to:  

Ad
Ad
Ad