Re: Finding CIELab Values from Target Chart TIF
Re: Finding CIELab Values from Target Chart TIF
- Subject: Re: Finding CIELab Values from Target Chart TIF
- From: Peter Skarpetis <email@hidden>
- Date: Thu, 29 Apr 2010 12:11:44 +1000
On 29/04/2010, at 12:07:28PM, Joseph Yates wrote:
> Dear List
>
> I have a 140 Patch Target TIF file that I don’t have access to the Reference
> CIELab values.
> The chart is used by PhaserMatch 4.0 (created by X-Rite for Xerox).
>
> Requests to both Xerox and X-Rite have not been fruitful and so I’m now
> wondering if their is a way to “extract” these values from the chart itself.
>
> I have opened the the Chart TIF in Photoshop and can read the L*a*b* values
> in the Info palette – but only as single digit L*a*b* values.
> Is there a method to obtain more precise (minimum 3 decimal places)?
The Lab values you are seeing in photoshop are just a simulation. They are calculated from the RGB / CMYK values in the tiff file using your current colour settings. This is assuming that the TIFF file is not an Lab file.
If you wish to have more precision, use photoshop or any other image viewing software to extract the RGB/CMYK values for the patches. You can then use Colorsync utility or any other such tool to extract more precise Lab values using CMYK/RGB profiles for the process you are trying to simulate.
Peter Skarpetis
>
> PhaserMatch exports (and imports) the measured (acquired) CIELab values as
> Lab D50 2°
>
> Regards,
>
>
> Joseph Yates | Pacifica Island Art | Maui, Hawaii
>
>
> _______________________________________________
> Do not post admin requests to the list. They will be ignored.
> Colorsync-users mailing list (email@hidden)
> Help/Unsubscribe/Update your Subscription:
>
> This email sent to email@hidden
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Colorsync-users mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden