Document ID: chunk:federal_register_of_legislation:F2024C00148:reg:1:p33
Version: federal_register_of_legislation:F2024C00148
Segment Type: reg
Provision Reference: reg 1 (pt 33/34)
Character Range: 225872–229241

the point light source detection factor PLSDF evaluate the luminance profile in horizontal and vertical direction (Figure 2).

              Figure 2
              Luminance profile of the rendered point light sources for the determination of PLSDF
              The point light source detection factor - PLSDF is determined by the following equation:

              Where:

                   sH full width at half maximum of the luminance profile in horizontal direction at the vertical centre

                   LH,max maximum luminance of the luminance profile in horizontal direction at the vertical centre

                   sV full width at half maximum of the luminance profile in vertical direction at hourglass point

                   LV,max maximum luminance of the luminance profile in vertical direction at hourglass point

              Verify the consistency of the result with slightly shifted position of the point light source lab model.

              For determination of the point light source contrast factor PLSCF, evaluate the luminance profile in horizontal direction (Figure 3) at the vertical centre.

              Figure 3
              Luminance profile of the rendered point light sources for the determination of the PLSCF
              The point light source contrast factor PLSCF is determined by the following equation:

              Where:

                   LH,max maximum luminance of the luminance profile in horizontal direction

                   LH,min luminance value at saddle point of the luminance profile, which is equivalent to the minimum luminance value between the two luminance peaks (see Figure 3)

              Verify the consistency of the result with slightly shifted position of the point light source lab model.

              1.4.  Grey scale rendering test method

              The grey scale rendering test shall verify that CMS are capable of displaying at least 8 tonal grey steps distinguishable within the darkest and brightest output range from the reproduced chart on the CMS monitor. The grey scale rendering test is evaluated using a 20:1 low contrast grey scale chart as described in ISO 14524:2009, Table A.1, under 500 lx illuminated scene environment.

              The distinguishable tonal difference described herein is defined as an display output signal whose lightness difference between two different tonal input through the CMS satisfy at least delta L* ≥ 3.0, with L* defined as lightness according to the definition in CIE 1976 L*a*b* colour space.

              Figure 4 shows the test arrangement for the grey scale rendering test.
              Figure 4
              Test arrangement for the grey scale rendering test
              1: Test chart (grey scale rendering chart)
              2: Illumination for test chart
              3: Camera being tested
              4: Monitor being tested
              5: Reference camera
                  6: Optical or spatial isolation between camera and monitor display environment
              7: Optical isolation barrier to avoid direct light into lens
              8: Camera-side
              9: Monitor-side
Figure 5 shows an example of a grey scale rendering chart to be used in this measurement. The grey scale rendering chart shall consists of 12 different tonal density grey patches.
              The density value