Filters have largely gone the way of the dinosaur with digital photography. Lens filters, that is. The simple fact of the matter is that they’re just not needed now. We used to need a whole array of filters when we shot film. Solid colours to shift the contrast on black & white film. Variously coloured graduated filters to shift skies warmer. Now, you can do all that in post.
Colour shifts and gradients are pretty straightforward in Lightroom or Photoshop. But one filter that’s still essential is a circular polarising filter. It allows you to do things that are simply impossible in post, even with today’s digital technology. This video from photographer Christopher Frost explains why, with some practical examples.