ColorAnt | Smoothing

Smoothing

Automatically Smooth Measurement Data

Smoothing Measurement Data

The Smoothing tool will fix inhomogeneous measurement data and bumpy curves. The tools uses an interpolation method that fits perfectly to already smoothed data. With the help of a slider the strength of the smoothing can be determined to fit the entire measurements into the mathematical model. The general characteristic of measurement data will be retained. When using the Automatic tool the maximum slider setting for smoothing will be used. Mainly the flexographic print processes exhibits a special bump curve in the highlights area. As this is a typical behavior of such printing systems, smoothing should not eliminate these highlight curves.

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To protect highlight areas, enable the Protect Lights option. The slider allows the percentage value for smoothing to be adjusted. Values below this slider are protected. In order to have a good transition from the protected and not smoothed highlights to the smoothed rest of the measurement data it is advisable to check the smoothing results when the Protect Lights option has been used.

Note: In the TVI View check to be sure that there are no hard edges introduced after smoothing. If there are, revert to the file before smoothing (use the History feature for this) and make sure to select a wider range for the protect lights option. For smoothing of the entire measurement data be sure the Protect Lights slider is set to 0%.

Note: Use smoothing only after having used the Correction tool first. Without applying the Correction tool the smoothing option may incorporate errors from the data into neighboring colors and not give optimum results.

ColorAnt | White – Black Correction

White/Black Correction

Apply Manual Corrections to Paper White

Correcting the White and Black Point

This tool allows to adapt the paper white with the White Correction and the darkest color with the Black Correction sections respectively.

The tool White Correction allows to apply manual corrections to the whitest color patch of the measurement data which is typically the paper or substrate color. The tool is to be used on a single measurement files. The correction in form of a modified Lab or LCh input value is helpful in such circumstances where either a certain target white point shall be reached or corrections are needed to lighten, darken or recolor the file. The manual correction is then applied to the entire measurement data keeping the print characteristic intact.

White Correction: predicts the impact of the paper white changes to the measured values of a test chart. With ColorAnt you are able to use three different methods to calculate this effect; ColorLogic Default, ISO 13655 and Relative Colorimetric.

White Correction Methods

ColorLogic Default: uses a spectral color model to apply corrections leading to the most realistic results. This works best if both the data that should be changed and the white picked from another file are spectral data. When no spectral data is available, ColorLogic Default proceeds like ISO 13655 and assumes that the shadows are not affected and that there is a much lower impact on the primary colors.

ISO 13655: similar in the highlights and colorful primary colors to relative colorimetry. However, this method assumes that the shadows and very dark colors are not changed.

Relative colorimetric: paper white changes will modify the entire color space. In cases of major changes in the paper white this will also strongly affect primary colors.

Black Correction: users can change the darkest black which will scale the entire data set toward the edited black point. Useful in situations where black has been measured to dark or to light compared to the visual appearance. Common scenarios include materials used in industrial applications like ceramics, textile, glass etc. Important: Black Correction is not available when using the Relative Colorimetric Method.

Procedure for White Correction:

  1. Load the measurement data that you want to change and the data containing measurements of the new paper white.
  2. Click on White/Black Correction
  3. Choose to adjust the corrections in LCh or Lab Color Mode. Change the mode at any time. LCh allows to adjust the hue or chroma independently whereas corrections in a* and b* will change hue and chroma simultaneous. The split color patch displays the original white on the left side and the modified white on the right side.
  4. Either manually edit the desired white point with the slider or by typing in Lab numbers or pick the new white point from the other data file using the eyedropper icon. Click on the eyedropper and select the other data file to automatically pick the new white point.
    Note: The eyedropper will pick the whites patch from the selected file. If spectral data is detected, the tool will use it according to the Method selected.
  5. Note: The sliders allow for small changes. More precise numbers can be entered in dialog. The sliders will reset after.
  6. When changing the Lightness (L* value) and using the Method Relative Colorimetric typically the darkest colors of your measurement files will be affected, too. If you want the black point and the darkest colors to not be affected, use the Method ISO 13655. Both methods, relative colorimetric and ISO 13655, apply calculations with colorimetric data. Only the ColorLogic Default, which is the default setting, will use the full spectral data and a spectral model for the calculation.
    Note: Depending on the color difference of the paper white and if optical brightener agents are available this can affect primary colors.
  7. Clicking the Reset button will discard your slider modifications.
  8. Clicking the Start button will apply your changes on the entire measurement file. The dialog will close automatically after calculation.

Procedure for Black Correction:

  1. Load measurement data.
  2. Click on White/Black Correction.
  3. Select either ColorLogic Default or ISO 13655.
    Note: Relative colorimetric does not allow changes to the black point.
  4. Adjust the correction in LCh or Lab Color Mode. LCh allows adjustment of the hue or chroma independently whereas corrections in a* and b* will change hue and chroma simultaneous. The split color patch displays the original black on the left side and the modified black on the right side.
  5. Either manually edit the desired white point with the slider or enter the Lab/LCh numbers.
  6. Click the Reset button to discard the slider modifications.
  7. Click Start to apply the corrections. The dialog will close automatically after calculation.

ColorAnt | Correction

Correction

Correct and detect faulty measurement

Correction

Detects faulty or “illogical” measured values and replaces data with proper measurement values. If the data is left uncorrected, inaccurate ICC profiles are often the result.

Important: For optimum results, Correction must be applied before the Smoothing.

Common measurement data issues:

  • Illogical measured data of lighter or darker gradation values based on adjacent colors.
  • Illogical data due to variations in the printing process or contaminated color patches (from the mechanics of the device) when measuring.
  • Instead of a red color value, there is a green patch.

Actions

  1. Correct bad measurements fixes the above mentioned common issues. This option should always be active when using the tool.
  2. Protects Lights allows selection to which percentage value the correction shall be performed. Values below this value are protected. The slider values range from 0% to 50%.
    Features for flexographic printing: The flexographic print processes often exhibits a bump curve in the highlighted area. These types of curves can be retained by using Protect Lights. In some flexo data cases it may not be necessary.
  3. Optimize overprints improves patches with overprinting darker colors such as tertiary colors. A subtractive color model is used for the optimization. In other words, the model assumes that adding colors leads to a darker color appearance. Some printing processes like electrophotographic and inkjet printers do not necessarily behave like this. In such cases, it is not recommended to use this option. We would recommend disabling this option unless you desire data that perfectly behaves subtractive.

Note: The Auto tool uses only the Correct bad measurements option.

ColorAnt | Redundancies

Redundancies

Correct Redundancies in measurement data

Redundancies

Redundant color patches can cause errors when creating profiles, especially if they have very different measurement values.
The Redundancies tool corrects the measured values of multiple color patches by averaging the redundant values. Corrected redundant color patches then have identical values.

The methods for correcting redundant color patches are the same as in the Averaging tool.

Auto: Different methods are used depending on the number of color patches. It is therefore quite possible that some color patches are processed with a different method than others. If there are two identical color patches with differing measurement values and one of the measurement values is recognized as an outlier, this method automatically selects the plausible color value.
For more than three color patches, the Weighted or Median methods are used. If there are a large number of measured values, both the Median and the Weighted methods consider values that are far apart to a lesser extent for averaging.

As the most intelligent method, Auto is preferable to the other methods.

Arithmetic: For the arithmetic averaging of values of several color patches, i.e. the average of the measurements (if, for example, only two color patches are to be averaged).

Median: Is a statistical method and denotes a boundary between two halves. The median is the “middle value” of a sorted list of numbers. Half of the numbers in the list are smaller and the other half of the numbers are larger than the median.

Weighted: Calculates a weighted mean value, i.e. a mean value to which some values contribute more than others. Outliers can be considered to a lesser extent for averaging.

Remove duplicate patches: Removes multiple color patches. First the average color value is calculated, then all but one identical color values are removed.

Note: The Redundancies tool can be used to average emissive data, such as multiple spectral measurements of a light source stored in a measurement file without DCS data. If the measurements are spectral, the averaging is performed on the spectral data.