Hartmut Bornemann's 2DPlot inspired this new script, a contour plot so you can see large-scale illumination variations in your flats quickly.
The plots are good for large-scale evaluation, but usually they show neither small-scale features nor low-contrast features such as dust rings.
The script works mostly for flats, but can also be used for darks and flat-darks to see fixed-pattern variations.
You will likely have to adjust the Resolution and Sigma settings. Use resolutions less than 100% so the entire plot is easily readable in its window at 1:1 zoom. Use small sigma values to get a nice balance between noise reduction and feature depiction. Plots of single subframes require more noise reduction than integrations. Use the Contours setting to change the number of contour levels plotted.
Thanks,
Mike
Here is an example of a flat integration. You can see that vignetting amounts to about 5% from center to corner:
Here is an example of a flat-dark integration. The fixed-pattern variations across the frame are visible.
The zip contains the script and examples. Tested for PixInsight 1.8 RC7 on Win7 and MacOSX 10.7.
https://dl.dropboxusercontent.com/u/109232477/PixInsight/Scriptbox/FlatContourPlot.0.1.zip
