X-Rite XRGA

[probep]

Gurus, what do you think about new XGRA standard and new X-Rite approach? About current spectrophotometers inconsistency and transformation matrices?
http://www.xrite.com/Documents/Literature/EN/L7-462_XRGA_Whitepaper_FINAL_EN.pdf
http://www.xrite.com/product_overview.aspx?ID=1336
http://www.xrite.com/product_overview.aspx?ID=1336&Action=support&SupportID=5356
http://www.xrite.com/Documents/Literature/EN/L7-476_XRGA_EN.pdf

[digitaldog]

I think its a good thing when you consider that the various manufacturers all come to this differently, producing different results when we end users assume they are the same. So its good. What’s “bad” is for those who have years of data measured, doing trending or similar work with older equipment that end up with newer equipment based on this new idea and don’t know the legacy data is no longer “valid”. There needs to be an upgrade path that takes existing data into consideration (some kind of matrix if you will that allows us to move our legacy data forward with the new measured data). I’m told this is doable, its just a pile of math. The question is, will such a solution be available?

[probep]

X-Rite has released ColorPort v2. It supports the XRGA standard.
http://www.xrite.com/product_overview.aspx?ID=1336&Action=support&SoftwareID=1028

[RachelK]

Hi Andrew,

You can find the complete information on the upgrade paths by product here.

http://www.xrite.com/product_overview.aspx?Action=support&ID=1336

[digitaldog]

You can find the complete information on the upgrade paths by product here.

http://www.xrite.com/product_overview.aspx?Action=support&ID=1336

So ColorPort will take my legacy data, measured from older units and update/convert for the new metric?

[RachelK]

Yes, it will. When you go to save out your data, you can choose either the legacy X-Rite or GMB conversion, or the XRGA conversion.

[jc1]

So ColorPort will take my legacy data, measured from older units and update/convert for the new metric?

No doubt previously measured data can be recovered from a saved Monaco session into ColorPort, unfortunately the spectral data (380nm to 730nm) cannot be restored. I wonder if actual spectral data were saved during a Monaco session at the very first place.
 
I believe the adjustment can only be performed on the current measurement but not on a previously saved session.
 
A quick check was performed as follows:
(a) Load data from a previously saved Monaco session.
(b) Output in both PM5 and CGATS formats and with options: XRGA, Former X-rite, Former GretagMacbeth
(c) Remove data format names (nm380, nm390, ...., nm730) from the save data in (b) or else PatchTool will read all 0's or Blacks
(d) Compare read data with PatchTool.
 
All data were identical and unadjusted.
 

[digitaldog]

All data were identical and unadjusted.
 

Its also not going to solve a particular problem we are facing with legacy data with differences, mainly in reading white with OBAs, between older and newer units (the newer ones now confirming to this new spec). That’s going to take some bigger math.

[probep]

The difference exists and is large enough.
I tested the ColorPort v2 with i1Pro measuring X-Rite ColorChecker, then saved the same measured data in according with new XRGA standard and with "legacy GretagMacbeth" convention.
Max deltaE between XRGA and "legacy GretagMacbeth" was 1.7

[digitaldog]

Max deltaE between XRGA and "legacy GretagMacbeth" was 1.7

That’s indeed too high for many. Hopefully there will be some conversion utility that would allow existing workflows to use the newer collected data in a backwards compatibly fashion (or maybe it could be a new feature in ColorThink!).

[WillConger]

Has anyone heard of X-Rite providing a way to convert a measurement of a single color, not just an ICC profile chart? I have hundreds of GretagMacbeth SpectroEye color measurements stored with a that I will need to convert when I upgrade my devices to XRGA. The Colorport solution doesn't seem to address this.
Also does anyone no more about what X-Rite has changed? Are they changing the white calibration tiles in GretagMacbeth devices?
I have also heard that XRGA will only apply to 45/0 geometry devices and not spherical. True?

Thanks,
Will

[digitaldog]

Also does anyone no more about what X-Rite has changed? Are they changing the white calibration tiles in GretagMacbeth devices?

White seems to be the biggest delta between older and newer collected data but I can’t say that’s all that is affected. Some software utility to convert is most needed. I’m told its doable.

[probep]

By the way not only colorimetric values are changed when converted to XRGA, spectral data of patches are changed as well by ColorPort.

[WillConger]

I spoke to X-Rite and came away with more questions than answers. Apparently they are not changing the white calibration tiles. If a device contains firmware it will need to be updated but whether this requires the device to be sent in or not has not been finalized. X-Rite's website says they do have to be sent in for service but the X-Rite rep I spoke to said they probably don't want a mountain of devices showing up so they may offer a remote update option. There is no final decision on whether X-Rite will provide transforms for spot color data either through their own software or through 3rd party software.

[jc1]

Am I correct to say the best color match for ColorPort 2 output is with the default saved option?

Device   default saved_option
I1pro:     xrga
dtp41:    formal x-rite (same as output from CP1.5.4)
938:       formal x-rite (same as output from CP1.5.4)

[WillConger]

Am I correct to say the best color match for ColorPort 2 output is with the default saved option?

Device   default saved_option
I1pro:     xrga
dtp41:    formal x-rite (same as output from CP1.5.4)
938:       formal x-rite (same as output from CP1.5.4)

I don't think there are better or worse, just different. What is your color management scenario?

[Mc]

This XRGA sounds like a good thing for the printing industry as a whole.

To put it in a nutshell, due to the poor the inter-model agreement between different brand spectrophotometers if I measured a chart to profile a printer with two instruments from different companies not only would I get different readings due to the relative precision of the spectrophotometers used, but readings would be even farther apart because of  the way that measurement are handled internally by the two spectrophotometers. Right? therefore, if I measured a red patch with an X-Rite unit and a GMB unit they wouldn't "see" the same red.
 
However, what is it going to change for photographers? Does it mean that It would be a good idea to put off buying a spectrophotometer before the current stock ends? Will the new spectrophotometers converted to this new standard be compatible with older applications like Profile Maker and Monaco Profiler?

Out of curiosity, any idea why they used just every spectrophotometers but the iSis?

Thanks in advance

Man

[jc1]

I don't think there are better or worse, just different. What is your color management scenario?

Best if there is less color difference between output from various measurement tools. No?
I've got all above 3 models. DTP41+MonacoProfiler is still my preference.

[digitaldog]

Will the new spectrophotometers converted to this new standard be compatible with older applications like Profile Maker and Monaco Profiler?

Its not the software mentioned that’s an issue, its the data you feed to the software products. And yes, we sure hope there is some conversion utility for legacy data. Supposed you have an older instrument and you’ve got years of data you measured for not only building profiles but for process control work (like what we see in the Chromix Maxwell’s product). You buy a new instrument, (even an updated one based on the older equipment or your older equipment needs repair or recertification). The new collected data is going to be different now. That’s going to be a real issue for you when you hope to mix old and new data. You’d want something that could be backwards compatible and/or a way to update the legacy data to comply with the new standard. So we need some software solution to allow an existing workflow to continue with this new captured data.

[Mc]

Got it! thanks Andrew