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Linear and Non-Linear in PixInsight
Hi guys. I've just switched to using PixInsight. As I'm working through a few tutorials I notice that my data seems to be non-linear already straight after stacking.
My image acquisition was done via Nebulosity as FITS files. I took completely unedited FITS files and did the calibration, star alignment and integration in Pixinsight. (one FITS is 107mb)
Resulting stack looks great, but it looks non-linear. When I open the histogram it already appears to have some stretching. I also don't actually have to use the STF (screen transfer function) to make my targets visible - it's there as if it's non-linear? So now I am unsure if processes like colour calibration actually works, or deconvolution.
Both stacks in PI and Nebulosity looks identical btw.
Could there be a problem in my acquisition?
Help appreciated. Thanks
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