NGC 1808 LRGB Processing Example

Video tutorial by Vicent Peris (OAUV/PTeam)

With raw CCD images acquired by Jack Harvey and Steven Mazlin (SSRO/PROMPT/CTIO)

Two parts – total time: 27:06


In this tutorial, PTeam member Vicent Peris describes some fundamental concepts and techniques that can be applied to almost any deep-sky image with PixInsight. Using a set of raw CCD images acquired by the SSRO team with a robotic telescope at the CTIO in Chile, Vicent shows us the complete procedure to perform the optimal LRGB combination of this data set. With special emphasis in achieving an accurate adaptation between the luminance and chrominance components, Vicent also demonstrates how to use some powerful features of the LRGBCombination tool in PixInsight, such as the integrated color saturation boost and chrominance noise reduction routines.

Besides LRGB combination, this tutorial is a complete processing example where many other tools and techniques are put into practice, including linear data visualization with the ScreenTransferFunction tool (STF), background modeling and gradient removal with DynamicBackgroundExtraction (DBE), color calibration with BackgroundNeutralization and ColorCalibration, nonlinear stretch with HistogramTransformation, dynamic range compression with HDRWaveletTransform, and chromatic noise reduction with SCNR. The tutorial teaches you good image processing practices that you can apply to your own images in the linear and nonlinear stages.

Vicent Peris is a member of the core PixInsight development team (PTeam) and works as an astrophotographer at the Astronomical Observatory of the University of Valencia, Spain (OAUV). He is currently leading some professional astrophotography and science outreach projects, including an imaging program in collaboration with Calar Alto Observatory, in Southern Spain, where he works with the 1.2 and 3.5 meter telescopes.


Raw Image Data

The authors of the NGC 1808 image used in this tutorial have kindly given us permission to provide the raw image data (four FITS files) and an XPSM file that you can use to perform in PixInsight the whole step-by-step process described in this video tutorial.

Important — Please note that the raw image data stored in the ZIP file above are copyrighted material being provided here for personal study and evaluation purposes exclusively. Any other use, including without limitation the public reproduction, online storage and generation of derivative works, is strictly prohibited without prior written consent from the authors.


Part 1 — Video duration: 11:40

Keywords: LRGB combination, background modeling, background neutralization, color calibration.

Tools: ScreenTransferFunction, LRGBCombination, DynamicBackgroundExtraction, BackgroundNeutralization, ColorCalibration.



Part 2 — Video duration: 15:26

Keywords: LRGB combination, background modeling, nonlinear stretch, histogram transformation, HDR wavelet transform, subtractive chromatic noise reduction.

Tools: DynamicBackgroundExtraction, HistogramTransformation, HDRWaveletTransform, LRGBCombination, SCNR.



All the material on this page is copyright. Feel free to use it for personal study or evaluation purposes exclusively. Any other use, including without limitation the public reproduction, online storage and generation of derivative works, is strictly prohibited without prior written consent from Pleiades Astrophoto S.L.