Spectral tools - Graph
|
|
|
|
The sample on the left (S1), drawn in black in the top graph, is an ambient measurement of a tungsten-halogen desk lamp. With a 2561 K color temperature, this illumination has a spectrum close to Illuminant A, and has a definite yellow tinge compared to D65 (the illuminant used for representing the color patch). The sample on the right (S2), drawn in red in the top graph, was measured in reflectance. The bottom graph shows S1 times S2, equivalent to what would be perceived if you looked at the S2 sample illuminated by the S1 light without being adapted to the light (i.e. if it looked yellow instead of white). Once adapted to the light, the reflectance sample will be perceived with a color much closer to the purplish color patch than to the orange color shown; to see the adapted color, you would need to click on the "W adapt." checkbox on the right of the bottom graph.
The above image is an example of what can be obtained by clicking on the "Save image" button located in the bottom of the Graph tools dialog. Here, the top graph shows two samples taken under a 4700 K SoLuxTM lamp whose voltage is boosted to increase the color temperature. The bottom graph shows the first sample, in black, compared to an ideal D-series illuminant of the SAME ILLUMINANCE, in green. This comparison was selected by clicking on the "S1 vs Illum." radio button located between the top and bottom graphs of the tool interface (see the top screenshot where this button is shown). D50 was manually selected as the ideal illuminant, but D48 could also have been automatically selected since it is closer to the measured 4824 K color temperature. We see a very good match between the two spectrums. The quality of the illuminant can be further analyzed using the ISO 3664+ tools shown in the next screenshots. |
|
Legal Information -
Privacy Policy -
About us -
Press/Media
|
