my 1st post..red cast on Lacie 324/CS4 RGB to CMYK

[TommyO]

Nadaman,
Not that this explains the CS4/CS3 difference, but after a bit of searching (actually a lot), the nVIDIA 8800GS for the iMac does not support dual monitor calibrations; it only contains one LUT for that purpose. The solution would be to add a second graphic card (which the iMac does not support), or determine which monitor will be the "calibrated monitor" and use the other for general purposes.

There are similar threads discussing this issue throughout the Apple support community... here is one of the many - (Apple Forum). Finding the specifications for the 8800GS from nVIDIA is a bit more difficult, as the 8800GS for the iMac is actually a slightly redesigned GeForce 8800M GTS. Hence, the spec's get a little intertwined.

The bottom line, even after resolving why the difference in CS4 vs CS3, there will still be an issue you need to resolve. I suspect that CS3 is behaving better with the graphics card. Maybe CS4 will also after nVIDIA releases another driver update, assuming they do so for an 18 month old platform.

The only item I haven't had time to look at is whether the LaCie contains a built-in GPU & LUT. I don't think so, but if it does, this poses another issue. Color values will be converted twice, once based upon the calibration and LUT in the 8800GS, and again as they pass through the GPU in the LaCie. Based upon the price point of the 324, I don't think it would contain a GPU of its own. So, this could be a null point. But, worth inquiring about with your contact at LaCie. If it does, you'll need to have a "null" LUT in the 8800GS card; I think there is a Mac utility to do this.

[nadaman]

Tommyo thanks for your time, much appreciated.

or determine which monitor will be the "calibrated monitor" and use the other for general purposes.

I would like my Lacie to be the primary calibrated screen.

I did pass on your question to Lacie yesterday and am waiting for an answer.
I have to admit that I'm in over my head on all this stuff.
I have looked at your Apple link briefly, but I've got a busy few days ahead with no time to research it.
And I have to prepare a photo for magazine repro today.
Based on previous posts regarding color performance of my screens, would it be safe to prepare my file using CS4, trusting my 324's manually activated custom profile and then switch to CS3 to do the CMYK conversion?
The difference between my Apple display and 324 with CS3 (in either RGB or CMYK, it is consistent) is that the Lacie is ever so slightly redder in the flesh tone - hardly worth mentioning. This would keep me working with some degree of confidence in what I'm handing over to the printer.

Going back to your link, I have AppleCare. Is this fix something that Apple can walk me through over the phone or at least is Apple the place to start? Again, I only read your link briefly.
If you have any other links regarding this issue, please pass them along.
I'll probably have time next week to tackle this and will be posting results here.
Please check back if you have the time.
Again to you and Markzebra, thanks for all your help.

[Markzebra]

Well done TommyO, looks like he's got your answer there.

Something basic has just occurred to me - if its graphics card related, try switching off Open GL - Preferences/performance/Open GL. Under Advanced in here there is also a checkbox for Gamma Correction , if you want to leave Open GL on, try playing with these settings also. Restart Photoshop is needed for these changes to take effect.

[TommyO]

Originally Posted by nadaman

Based on previous posts regarding color performance of my screens, would it be safe to prepare my file using CS4, trusting my 324's manually activated custom profile and then switch to CS3 to do the CMYK conversion?

Yes. And, agreeing with Mark, the conversion in CS4 should be fine as well. No need to swap to CS3 to do that. It's simply the viewing of the file in CS4 on that graphic card that "appears" to the eye to be different. Hence, you may want to use CS3 to view the final version and ensure it is to your satisfaction.

Originally Posted by nadaman

Is this fix something that Apple can walk me through over the phone or at least is Apple the place to start? Again, I only read your link briefly.

Maybe. If Apple is aware of an updated driver for the graphic card which addresses the problem, they can. Otherwise, your option is to replace the graphic card with a different model, which they may or may not warranty under AppleCare.

The more I thought about it, the less chance I think there is that your LaCie 324 has an internal GPU. If it did, I think they would certainly advertise it that way; when manufacturers say nothing about it, it implies they do not. Hence, you should not have to worry about nulling out the LUT. However, I would ask Apple how to best ensure the profile for the LaCie is always loaded properly, and not overridden by the internal monitor profile. This will depend on their experience with the nVIDIA 8800GS card.

[Markzebra]

would it be safe to prepare my file using CS4, trusting my 324's manually activated custom profile and then switch to CS3 to do the CMYK conversion?

As I said many times in this thread CS3 and CS4 are not doing your conversion differently. What happens behind the scenes in Photoshop is not related to what your montor is displaying. If you dont believe this CHECK both conversions. Using the eyedropper

With Open GL Off I'm pretty sure Photoshop CS4 will display colors in the same way as CS3.

[nadaman]

TommyO & Markzebra,
had moment to look at Apple link from TommyO's post. In it "Kees5" is talking about his ATI Radeon HD 2600 Pro graphic card. His iMac appears to be a 2007 model.

My NVIDIA GeForce 8800 GS appears , to me anyways, to support 2 LUTs.
Please see attachment.

Go to Display Preferences and these windows appear. One in Lacie display &
the other in the Apple display. As seen in jpg, you can check "show profiles for this display only"
box and it does do it.
Did Apple then fix this issue with card change? I don't mean to question your research as
I have not spoken with Apple yet.
I used my Blue Eye software (with measuring device) on the Apple display to create the profile seen and adjusted the monitor brightness to match the 324.
I duplicate a file, open both & place one on each display for comparison using CS3 & both files RGB. The images appear to be similar in density/brightness with the Apple display showing a slightly redder flesh tone which is no big deal.
Do not confuse this with 324/CS4 RGB to CMYK red cast issue which is a big deal.
The reason for 2 profiles - one for each display - I can't remember.
If I try to use Lacie's profile on iMac now, Apple display goes way to bright.
I would have to play around to see if one profile is possible for both displays.
Again I have not talked to Apple yet to confirm LUT issue.

[Markzebra]

I used my Blue Eye software (with measuring device) on the Apple display to create the profile seen and adjusted the monitor brightness to match the 324.

No you should create the profile AFTER you change brightess. Monitor Profiles record gamma, any change to monitor settings after you created the profile will invalidate it.

Did you try Open GL?

[nadaman]

point taken Mark but with the intent of 324 being my primary screen and iMac display for palettes,
I didn't think it a big deal at the time.
Going out of town today back on sunday. I'm going to call Apple then.
I'm also going to set up my old work station - IBM Powerbook w/ Lacie 19"blue CRT.
Have CS2 on that machine and am interested how the flesh tone color looks on that.
At this point I need to confirm 324 and iMac display are showing what the numbers say they should be showing. The portrait in this thread has a magenta/yellow spread of only a couple points max (some places even) in lighter areas of woman's face with a less than 10 point spread in the shadow below the nose. That flesh tone should show closer to red than yellow or closer to a baby's flesh colour rather than a tanned adult. hopefully seeing all three side by side may clear things up a little.
I have located OpenGL in CS4 preferences - performance, I will try it out sunday and let you know.
thanks, talk soon.

[TommyO]

Originally Posted by nadaman

In it "Kees5" is talking about his ATI Radeon HD 2600 Pro graphic card. His iMac appears to be a 2007 model.

While his was older, he refers to upgrading. Then others then refer to issues with the 8800GS. If you put "8800GS" in their search engine, you get a dozen or more threads with issues on the 8800GS - everything from calibration issues to OpenGL issues.

So, you may consider focusing on the card as the root of the problem. If it was CS4 or the iMac platform, I believe you would see a lot more traffic on the issue.

Again, your resolution will be to either find a driver update, or replace the card with another model.

Best of luck !

[nadaman]

Quick note FYI (I'm still busy):
1. Waiting on reply from NVDIA from email I sent. I have been passed on to level 2 support.
2. Confirmed with Apple that my iMac does support dual monitors - mirrored and extended desktop. If I want to replace the graphic card, I must buy a new mother board as well. They are attached in iMac.
Cost could be 2/3's price of new computer between the two.
3. Adobe called to say my case has been elevated to level 2 support. They could not tell me when level 2 would call with update.
4. LaCie looked at my calibration reports and confirmed they were good.

My short term work around is to work file in RGB using CS4, switch to CS3 for CMYK conversion.
I will post as I hear back from above.
Thanks for your patience.

[TommyO]

Thanks for the feedback.

Originally Posted by nadaman

Confirmed with Apple that my iMac does support dual monitors - mirrored and extended desktop.

This just means the graphic card has two outputs, which is true for 98% of the cards today. So, unfortunately, it does not imply the GPU supports dual LUT's, which is required for dual calibrations.

Originally Posted by nadaman

If I want to replace the graphic card, I must buy a new mother board as well. They are attached in iMac.

I wondered about this, and was not quite sure. Most applications for the GeForce 8800M GTS are mobile, which raised the question of what was inside the iMac. (I've never opened one up.) Thanks for letting us know this as well.

This also begs the question of whether or not you can switch the primary display. Not very likely in this configuration. So, Apple must answer the question... "how do you calibrate the secondary display on an iMac with this GPU ?"

[ReneDamkot]

Late to the party (came across this thread Googling for something else).

The first screenshots (CS3 and CS4 on the LaCie) have the iMac monitor profile embedded (10.06.09-5000k-22-110cd-PE-imac.icc) instead of the LaCie profile.

So that's not correct right there.

I suspect PSCS4 sees a different monitor profile from the rest of the OS and CS3 (had a similar problem once: Photoshop used the proper profile, OSX didn't: Turned out to be some kind of permissions issue)

Check what monitor profile both versions PS are looking in the PS color prefs here:

http://img.skitch.com/20090822-th5hk...atbmpydh2r.jpg

On a side note: I think (but am not sure) iMacs are similar to MBPs: Only one of two screens can be calibrated. The last screen calibrated will be accurate.
Would be fairly easy to check by measuring the accuracy of the profiles I think. (Should also be visible while calibrating, as the data is loaded to the LUT, only one screen should change.)

[nadaman]

BIG NEWS, PROBLEM SOLVED!
I turned off OpenGL in CS4 preferences - performance and CS3 & CS4
both behave identically in RGB & CMYK. LaCie red cast in CMYK is gone.
"Enable OpenGL Drawing" in preferences is new in CS4.

MarkZebra was right. Wondering if you could explain.

My apologies for not trying this (simple solution) out sooner but I had a deadline and choose to go with what I knew to work to get me by in the short term.
I have spoken to Apple again to confirm what the first product specialist said from post above.
I have not heard back from Nvidia or Adobe.

I would like to thank MarkZebra, TommyO and the others that contributed , I couldn't have done it without you as I have limited knowledge about all this stuff.

I will post results from my conversation with Apple later today as I have time now.
Again thanks all for your help.

[Markzebra]

Ok then we finally got there. Its to do with your graphics card having different colour rendering to Photoshops inbuilt. If you click on Open GL settings -Advanced there is a setting for 'Gamma Corrected'. You may find that turning open GL ON again and playing with this setting might help you to use Photoshops new Open GL settings without problems.

Photoshop CS4 has two ways of renderigng on screen - one is using your graphics card, directly using Open GL - and the other is built into Photoshops code, just as it always was in previous versions

[nadaman]

To TommyO:
I spoke with Apple a second time to find out more about dual monitor support.
Here's what was said,
- my imac has full dual monitor support with 2 LUT's that treat both displays equally.
- rearranging the displays is easily done in display preferences, under arrangement.
can also drag menu bar to any display. see jpeg of arrangement talk window.
- calibration profiles are also supported for each display with the 2 LUT's.
- when I asked if I could use 1 calibrated profile for both monitors he said it was
highly unlikely because even though both would be LCD displays, they are made
differently by each manufacturer. Like comparing lenses. Both may be made of
cut glass placed in a barrel but their performance could be quite different based on
the glass used, coatings, and design.
- this rep said the motherboard and video card were separate. He was looking in the spec
manual. But one could run into a problem with the connection between the two.
A newer GPU may not have the same connector to allow it to be hooked to an older
motherboard, which may very well lead to the motherboard being replaced as well.
The work would have to be done by an Apple trained service provider to keep the
warranty valid.
- He also said there would be no advantage to having 2 GPU's - one for each display - for
still images. Dual cards could help in graphics acceleration (gamers). But only in the highest quality
monitor one may notice only a slightest difference that he felt didn't justify the cost of the second
card.
Hope this answers your questions. Thanks for all your help and information. I now know a lot more.

[nadaman]

Thanks Mark, I'll have to give it a try. cheers.

[TommyO]

Great !
Nice to know the resolution was that easy. Many OpenGL issues show up as more complicated or obvious. Interesting this one was very subtle. One day we may know more about why; or they'll build proper support into all the graphic adapters, so it won't matter.

[warze li]

…dont thrust in your display to much! …this "magenta" issue is very common in print world…u need tht ur "print" provider gives u an indicative profile…(i most use "ISOnewspaper/coated FOGRA39 and modified spaces", but tht is given me from the printprovider) …for better prints… (and i still correct skintones allways, separatly with a "quickmask"… and lot more… put out tht cyan from red/yellows…in commercial print skindarkness st looks "better" if you replace cyan with black, …cleaning out most of colors… so they more "understandable"…blacks need particular attention…neutralizing…and…working much with "blur" and "unsharp mask"…always look your prints are at right dpi when printed …ask how they print…try visit!…)…
…all tht trying to not alter the image to much from his origin…and doing good predictable image preparation for specific print…u know u can do it…
…u need request a color proof from your provider to…so you can REcorrect where u wrong «and work "with" tht profile…instead suffer from misstakes…a proof not costs a wrong print! …then u have better results!……but im still learning…