cschmeer wrote:If I am mainly shooting interiors of old buildings for an upcoming project, will the polarising effect from the Fader ND filters have negative visual effects in situation (or is there more of a problem with skin tones, skies etc.)?
Since a polarizer (including in a "variable ND") mostly affects
reflected light, it affects every scene differently -- as the light changes, as surfaces change orientation, with different surface textures/reflectivity.
When in doubt, test.
In general, you can't know whether a polarizer's effect is negative or positive for a particular scene until you try it, although there are people in both "camps": Some say you should avoid using polarizers except when absolutely necessary, and use a conventional ND filter instead of a "variable ND". Others say don't worry, be happy, especially as long as you use a very good "variable ND" such as Heliopan.