This gizmo is based around a keying technique that uses the IBK keying nodes with in nuke. Instead of using one IBK Colour, you use multiple ones stacked upon each other to slowly patch all the holes in the generated clean plate. The great advantage to this is that instead of doing one large patch, you do it in many steps that allows more detail to be retained. The gizmo allows you to adjust your dark areas and erode, it also facilitates for adding additional mattes to areas which have small detail, like hair for example. Once you have your settings in place, instead of having to copy and paste many nodes and increasing the Patch Black slider manually, just check the ‘Execute Stack!’ checker box.
The IBK S or IBK Stack, was inspired by a great tutorial given by CreativeLyonsTUTs – https://www.youtube.com/watch?v=izwwic6Q7cs
Download the nuke script from the link below.