LINEAR NOISE PATTERN

Object: M42.
Camera: Canon EOS Digital Rebel XSi - Type I Filter
Telescope: William Optics 132 FLT - Focal Length 925 mm - f/7
Number of Captures: 15 x 10 minutes. ISO 800.
Total time:  150 minutes.
Program: PixInsight.
Comments: Crop 1200x795 scale 1:1
Acquisition to 24ºC. To this temperature, in expositions longer than 4 minutes, they appeared the vertical lines that could be seen in the following picture.

 
Individual Frame - 10 minutes exposure.
STF Automatic - Not Linked RGB Channels

After calibration with MaterBias and MasterDark there are no hot pixels but the lines are still there. 
Calibrated Individual Frame with MastreBias and MasterDark
STF Automatic - Not Linked RGB Channels

The lines are very intense in Red channel, slightly less in the green channel and they do not appear in the blue one.

Red Channel


Green Channel

Blue Channel

With the Script developed by Enzo De Bernardini two patterns are generated, "Brilliant" one coinciding with the line of major sheen and "Dark" coinciding with those of minor sheen.

To create it, they were considered the median's values in a vertical line of average sheen of a pixel by the high of the photo in the center of the image.

As the blue channel does not have the lines, the value stayed in zero (0).

Brillant Pattern (STF)

Dark Pattern (STF)

Zoom

With PixelMath the Brillant is subtracted and the Dark one added contemplating two variables, the "weight" and the "adjustment".

The "weight" considers if 100 % of the pattern will be subtracted or added and the "adjustment" makes it relative to the intensity of sheen along a line.

The temperature change along 15 frames did that the "weight" was changing in almost all the images.

Calibrated Individual Frame and reduction of the linear noise with LinearPatternGenerator
STF Automatic - Not Linked RGB Channels

Integration of 15 frames x 10 minutes
STF Automatic - Not Linked RGB Channels

Processed Image (not using HDRComposition)

Used Processes:
DynamicCrop

BackGroundNeutralization
ColorCalibration
ACDNR (StarMask)
Deconvolution (StarMask)
MorphologicalTransformation (BackGroundMask)
GREYCstoration (StarMask)
HistogramTransformation (STF Linked RGB Channels)
HDRWaveletTransform (LuminanceStarMask)
ColorSaturation (LuminanceBackgroundMask)
LocalHistogramEqualization
UnSharpMask (StarMask)
GREYCstoration (StarMask)
MorphologicalTransformation (BackGroundMask)
SCNR
HistogramTransformation (LuminanceMask)
AssignICCProfile