The precise vapor deposition technology used in Hoya PRO ND filters results in a neutral color balance, which does not cause any noticeable discoloration in the images. So it is enough to adjust the white balance once and you can be sure that you will get the same color balance if you have to change filters, or the lighting changes, or just for creative effect.

This ND filter also has the same weakening effect on infrared rays, which otherwise cause discoloration, as it does on the visible range.
The latter feature makes the color balance of PRO ND filters even more neutral.

The goal followed when designing neutral density filters was to reduce only the amount of light entering the objective, while having no other effect on the image. And reducing the light intensity allows you to choose wider apertures or even longer shutter speeds to achieve the desired creative or dramatic effect even in strong lighting.