No problems stacking in PixInsight. As I suggested, the files are linear (not stretched) so you need to do a screen stretch to see what is there after stacking them.
What I did was:
- StarAlignment to register the images against a reference image (I picked "Calibrated-Color-T3-pb8010-ngc6960-20131129-203221-Color-BIN1-W-300-001" at random. Normally, I would go to some trouble to pick a good image as the reference. All other parameters were the default. The aligned images are written to a directory.
- ImageIntegration to stack the registered images. I used the default parameters and selected Winsorised Sigma Clipping as the rejection algorithm (it is generally a good choice for a dozen or so subs). I set Sigma low at 4.0 and Sigma high at 3.0. Normally, I would tweak these parameters carefully...
- Screen stretch with CTRL-A
- Copied the stretch from the ScreenTransferFunction process to the HistogramTransformation process and applied it to the integrated image (then reset the Screen Transfer Function)
- Saved the file as a Jpg and resized for upload to IIS.
I attached the resized stacked image and a screen shot showing the processes I used. Hope this helps...
As I originally suggested, the only thing you probably missed was doing a screen stretch after the integration. Data out of the camera is in linear form - the values in each pixel are a linear representation of the numbers of photons captured. Our eyes don't work that way. We see light logarithmically and the raw data needs to be stretched. In PixInsight you can do a screen stretch to see what the data looks like with the ScreenTransferFunction process (CTRL-A does an automatic STF on the current image). To make this a permanent stretch you need the HistogramTransformation process.
Cheers,
Rick.