The ColorCalibration process automatically calibrates the colors in your image based on a sample of white pixels and background pixels. You can provide the sample of white pixels or can allow ColorCalibration to acquire the sample on its own based on the entire image. You should provide a background sample, and you can reuse the sample you used for BackgroundNeutralization.

Once calibrated, your image should not have a color cast to it and you should be able to use the STF Auto Stretch in linked mode.

You use ColorCalibration when your image is still linear and use it after you use BackgroundNeutralization on your image.

Using ColorCalibration

  1. Ensure you have a linear image open on your PixInsight desktop
  2. Start the ColorCalibration process, you can find it under Process – ColorCalibration
  3. In your image, find a suitable white reference. If you leave this at the default, ColorCalibration will automatically determine the white reference. Your white reference can be a star or a galaxy. You can set this here or use the Region of Interest to save the reference along with the history state of the image
  4. Leave the options in Structure detection at their defaults, unless ColorCalibration is having trouble finding stars in your image
  5. Set the background reference – you can select it here or use the Region of Interest to save the reference along with the history state of the image
  6. Drag the New Instance icon to your image to calibrate it

If ColorCalibration does not produce a suitable result, try to adjust the upper and lower limits for the white reference and background reference images, also try adjusting the number of structure layers. You can also check the mask ColorCalibration is using by enabling the Output background reference mask option.

Conclusion

In this article, you learned about the ColorCalibration process and learned how to use it.

More Articles In This Series

This article is part of a whole series of articles about processing images using PixInsight. Get the index article here, which explains an entire workflow for processing an image using PixInsight along with several useful scripts that make processing a lot easier than processing manually.