Heliopan Vari ND filter will it polarise

Has anybody used one of these
they seem to be 2 polas stacked on top of each other

My main question is
are they just going to nd or are they going to polarise as well

I plan on using them to bracket exposure and I don't want anything else to change

thanks

robin

It will not cut down reflections in glass or water, it will just give you a (variable) ND filter.

Hmmm... never used the heliopan version, but I had made my own version stacking 2 polarizers once.

If the heliopan version allows you to move both layers of the filter independent of each other, it could work. It would be as if setting the rear polarizer (closest to the lens) to the correct angle to polarize the reflected light(and therefore reduce reflections), and then turning the front polarizer (farthest away from lens) to your desired ND density.

If the heliopan version only allows you to move the top polarizer, and the bottom one is fixed(which would make it a slimmer design and reduce the chance of vignettes) it probably wouldn't work.