[Lcms-user] Re: You said....

[<ma...@li...>]

Hi,

This depends heavely on what camera.icc is doing.
Probably is using D65 as white point.  Is this a profile
created for your specific camera or a generic one for
this camera model?

Besides, do you have tried absolute colorimetric intent?

For dealing with numbers seems more appropiate that
perceptual one. Also, what illuminant (lamp) are you
using? D65 is near daylight...

lcmslabi.icm is just a identity profile, that is, dumps contents
of PCS to output.

The dE induced by the CMM is very low, about 0.004 but
of course profiles are not perfect at all. A dE below 4 can be
regarded as "very good" on cameras. On monitors, numbers
are somehow better, and dE < 2 can be reached without
excessive problems.

Marti.


----- Original Message -----
From: "Bernardo Pucci" <cyb...@ti...>
To: "Martí Maria" <ma...@li...>
Sent: Wednesday, June 20, 2001 4:56 AM
Subject: You said....


> Dear Maria,
> thank you for your kindness.
>
> But I have a last problem, you said "lcmslabi.icm is using D50", but.
> for a test I shoot   the Macbeth ColorChecker to provide a camera image
that
> I
> save for the profiling target, I use the lcms with
> inputprofile="camera.icc" (with perceptual intent) and with
> outprofile="lcmsLabi.icm",  so for deltaE_Lab's measures I ought to use
the
> Macbeth's
> Lab value that are tabulate for D50.
>  But I don't understand because I obtain  a best  result when I use D65
> Lab's values   instead of when I use  D50 Lab's values.
>
> Which is a good value for deltaE_Lab (that you have tried with lcms)?
>
> I hoping to hear from you soon.
> Bye Bernardo
>
>
>
>
>
>