Filters vs. Post-Production: Why Photographic Filters Still Matter

An image of Kirkjufellfoss in Iceland created using 6 Stop ND (to drag the shutter), Circular ND (to remove the reflection in the water) and 3-Stop Graduated ND (to balance the highlights in the sky against the much darker foreground). Post-production involved stitching the images together in this 4 image pano stitch.

Once you move beyond the basics of photography and begin to take your craft seriously, you’re likely to encounter a key decision: should you use physical filters to control light at the moment of capture, or simply rely on the power of digital post-production? In today’s world of powerful editing software, it’s a common question — and one worth unpacking.

Photography forums, YouTube channels, and online tutorials are awash with tips on how to blend exposures, adjust highlights, and pull back detail in software like Photoshop or Lightroom. There’s a divide among photographers — some insist that everything can be done in post, while others argue filters remain essential tools in the field. The truth is more nuanced.

You can watch the video about Filters vs Post-Production by clicking on the link above.

Maletsunyane Falls on Lesotho photographed using a 2-Stop Hard Grad filter and 3-Stop ND filter.

Why Use Filters?

Let’s start with a simple premise: modern cameras and lenses are designed to be used as-is, without additional glass in front of them. So why, then, would any photographer deliberately place a filter over their lens?

Because certain effects just can’t be replicated effectively in post.

The Power of the Polarizer

One filter that no photographer should be without is the circular polarizer. Polarizers work by allowing only specific rays of light to pass through the lens to the sensor, significantly reducing glare and reflections. When rotated, they can darken blue skies, cut through reflective haze on water or leaves, and increase color saturation in a way that digital editing simply can’t replicate with the same precision.

Think of photographing a forest after rain — with a polarizer, the greens become richer, deeper, and the reflections from wet leaves are dialed back, revealing true color and contrast. You can tweak contrast and color in post, of course, but you can’t “digitally remove” the physical reflection captured by the sensor.

Use of a circular polarizer has helped remove the reflection from the foliage of these trees near Leeds in the Hill District of the UK. This makes the forest feel deeper and more wooded to the viewer.

Neutral Density Filters and the Art of Painting with Time

Next up is the neutral density (ND) filter — a tool that reduces the amount of light entering the lens. ND filters are especially useful for long-exposure photography, allowing you to blur movement in clouds, waterfalls, rivers, or waves. The effect can be ethereal and dreamlike, and it’s difficult — if not impossible — to truly mimic in post.

Technically, you could blend hundreds of images together to simulate motion blur, but the result often lacks the smooth, organic quality of a true long exposure. Plus, the process is time-consuming, and subtle motion jitter often gives the game away.

ND filters come in various strengths, measured in stops. A 3-stop ND might reduce a shutter speed from 1/125s to 1/15s, while the famed “Big Stopper” — a 10-stop ND filter — can allow exposures of several seconds or even minutes. This opens up creative possibilities: silky smooth oceans, cloud trails, or even ghost-free architectural images where people vanish due to their movement during the long exposure.

For video shooters, variable ND filters — which work like polarizers — are invaluable. They allow filmmakers to maintain a specific shutter angle or exposure in changing light conditions without affecting aperture or ISO. While less critical for stills, these filters offer tremendous versatility and control in the field. Although for stills there are a few caveats attached to using a variable ND filter. The most critical being that the polarization affecting blue skies with wide angle lenses and effectively applying the neutral density effect unevenly across the sky (it leaves a dark corner on one side of the sky).

Quiver trees photographed near Keetmanshoop in Namibia with a 6 Stop filter and Circular Polarizer to drag the shutter speed back to 30 seconds.

Graduated ND Filters: A Dying Art?

The one filter that can be convincingly replicated in post is the graduated neutral density filter. These filters are dark on one end and clear on the other, and are used to balance exposure between a bright sky and a darker foreground. In the days of film and its limited exposure latitude, they were essential. Now, digital blending or exposure bracketing allows photographers to take two shots (or more) — one for the sky, one for the land — and merge them in Photoshop and other editors.

Still, grad filters can be helpful in-camera, especially for video where bracketing isn’t an option. They also allow real-time composition and exposure balancing without relying on later editing.

Graduated ND filters - or ‘grads’ for short - come in varying strengths and transitions: hard grads for flat horizons like seascapes, soft grads for mountainous terrain. To use them effectively, a square filter system is required, which is often more expensive and complicated than circular filters.

The new JetMag filters from Nisi are great since they are so easy to use. Up until recently they lacked a solution for using grad filters though. Now there is a JetMag adapter that adds a 100mm square filter holder so that grads can be used once more. An awesome addition to filter users who enjoy or rely on using these filters for their landscape photography (I am one of them). 

A Nisi 3-Stop Medium Grad has helped control the bright highlights of the early morning sky against the darker foreground rocks. Photographers do need to be careful about darkening objects on the horizon line, as is the vase with the Umhlanga Lighthouse here.

Making things Blurrier

Finally, there are also a range of mist filters which are really useful in video shooting, as well as when photographing the Night Sky. At the moment it’s a little in ‘vogue’, but their is a specific look created by using something called a ‘black mist’ filters which smooths out contrast and gives a really nice looking falloff of light to specular light sources (which also makes stars look bigger, and why night photographers have started using mist filters for their photography - the Star Soft filter from Nisi is a specialist type of mist filter). Again, although it is technically possible to replicate the look of the filter in post-production, it’s never quite hte same and also requires additional time in post to be able to get the effect right. 

These Fony Baobabs near Andavadoaka in Madagascar were photographed using a Nisi Star Soft filter to make the brighter star appear that much larger.

Filters vs. Post: A False Dichotomy

Ultimately, the debate isn’t about choosing one over the other. Filters and post-processing are both tools — and powerful ones at that. Physical filters allow you to control light before it hits the sensor. They help you get the image closer to your vision in-camera, minimizing editing time and preserving image quality. Post-production, meanwhile, lets you fine-tune and perfect your image after capture. 

As a working photographer, I use both. I’m a filter advocate not just because I’m an ambassador for a filter brand, but because filters help me spend more time behind the camera — and less time in front of a computer. Ultimately, that’s where I want to be; standing behind a tripod somewhere awesome as the light explodes in colour, not in a deskchair staring at a glowing screen. 

So, while editing software continues to evolve, filters still offer unique, irreplaceable advantages. Whether you’re looking to polarize reflections, extend your shutter speeds, or control dynamic range in video, filters remain an essential arrow in the quiver of every serious photographer.