5 Replies Latest reply on Aug 14, 2008 9:56 AM by (Jesko_Oeynhausen)

    ACR RGB2XYZ Conversion, basic function

      Hi

      I am trying to understand the color conversion chain when I am using DNG + ACR.

      I simulated all the steps that are described in the DNG Spec and displayed the results in a CIE-xy diagram, but the result doesn't make sense.

      I extracted the matrix, written in the ColorMatrix2 Tag of the Leica M8, (i know that his matrix is used by ACR and makes good results). This Matrix Iis called A,

      The matrix I transform to the inverse Matrix to get the RGB2XYZ matrix.
      B=Inv(A)

      There is no CameraCalibration Matrix or AnalogNeutralGain, so these don't have to be taken into account.

      When I calculate the primary colors of that matrix using (r g b ) * B, I get a triangle that is shifted quite a lot .
      The whitepoint (RGB=111) is on the purple line of the spectral colors

      It looks like there is a vector, that I don't take into account.
      Can anybody tell me, what I am doing wrong?

      Thank you very much, Jesko