Color Calibration – Better Images with the Basler MED ace

4 November, 2019.

Color and–above all–its correct reproduction play a particularly important role in images in the Medical & Life Sciences sector.

For best color reproduction, cameras need the right settings. The search for the “perfect” color settings, however, is usually very complicated. The Basler Color Calibration Tool in the pylon software offers a simple and quick solution for this otherwise very complex task.

Why is color calibration so important?

Colors often form the basis of a medical diagnosis and thus drive crucial decisions on the prescription of medication or surgical interventions. In ophthalmology and dermatology, but also in microscopy, color is an important criterion for assessing whether a structure is healthy or diseased. For example, tissue discolors if it is not sufficiently supplied with oxygen. In order to ensure the reliability of the color rendering, the camera must be calibrated in the examination device.

How does color calibration work?

During the color calibration of the Basler MED ace, the parameters within the color calculation pipeline of the firmware are optimized. The basis for the calibration is the color defect ΔE. A chessboard-like table, known as a ColorChecker, is used for the calibration. It shows different colors and grayscales in squares. The sRGB values of the individual fields of the ColorChecker with certain illumination are known and serve as a reference for the color measurement value of the camera.

If you measure the color value of the camera for a certain field, you get an sRGB value, which you can compare with the actual, known value for the color field. The difference between measured and known point in the color space is given as color defect ΔE. In the calibration process, the individual function blocks of the color pipeline of the camera are now parameterized in such a way that the color defect is minimized in comparison to the reference values of the ColorChecker.

The color defect indicates how good the color representation of a camera is. A color difference of ΔE < 1 is hardly perceptible. If ΔE > 1, a very small color difference is perceived and if ΔE > 5, a different color is perceived.

Would you like to know more about this topic? Read the Vision Campus article from our partner Color Calibration in Medical Technology. And if you need technical information about your Basler MED ace camera, or the Basler Color Calibrator does not work as expected, please contact our experts from our technical team. They will be happy to help you.