In Symbology tab of a raster in ArcMap, in the section of Pan-sharpening, there is an extra option to check at the bottom: "4th-band Infrared Image" along with its weight:
I guess I have to add a 4th band while using "Composite Bands" tool, then give it a weight and so I will be able to see RGB mixed with IR view.
What is the difference or advantage of using it over eg. CIR or 5-4-3 (Landsat 8)?