This is a brief overview of why you need filters for landscape photography, comparing the different types of systems you may encounter, and breaking down which setup is right for you.
Whether you're just starting on your photography journey, newly dabbling into landscape photography, or looking to upgrade your filter system, there should be something here for you. Decision fatigue is a real thing, especially when it comes to the world of photography. Trying to decide what brand to get, which lens is right for you, primes versus zooms, full frame versus mirrorless, it feels endless. Filters are no different, and I distinctly remember being so overwhelmed when I first started that I just avoided them altogether.
My goal for this article is to get your feet wet and provide extra resources for exactly what you might need for where you are in your work. Let's start with the basics.
Why You Need Filters
There are two main reasons to use filters. The first is to create movement in your images by manipulating the shutter speed (think moving water or clouds). This is accomplished using what are called neutral density (ND) filters that essentially block light from your camera. Standard values you'll find most often are 3, 6, and 10 stops of light.
Another very important task filters can do is manipulate the physics of light, which is just a fancy way of describing the purpose of a circular polarizer (CPL), which is to cut out reflections of light on your subject or in the atmosphere. This is the most important filter you'll have in your bag as a landscape photographer, and if you're wondering just what it can do, check out my article that explains everything you'd want to know about a CPL.
Lastly, filters can manipulate your exposure in specific areas of your image, which is what you do with a graduated neutral density (GND) filter. These typically darken the edge of your frame and get lighter gradually. You'll see some referred to as "soft" and "hard," which just describes the transition rate from dark to light. Other filters exist to add “mist” or special effects to your images that I don’t even consider options, but they do exist.
Square Filter Systems
You're likely familiar with circular filters, as they have existed for nearly as long as photography. Square filters are a bit more unique and are only really present in landscape or architectural photography. Unlike circular filters that screw onto the threads at the end of your lens, these square filters require some type of system to interface with and attach to your lens.
There are a lot of options out there for systems, but they all function similarly, typically housing a large circular polarizer closest to the lens and then some type of apparatus that interfaces with square filters. This allows you to do a few things you can’t do with circular filters. Most importantly, it allows you to use graduated filters so that you can adjust the exposure of something like your sky without affecting your foreground. For decades, it also allowed you to stack ND filters much more easily than circular filters, but that has changed a bit with modern circular filters (more on that later).
A huge benefit of square filters over circular filters is in their size. One issue you can run into when using circular filters is vignetting at wide angles, especially if you're trying to stack filters. This doesn't happen when you're using these 100mm x 100mm square filters. It also means you can use these in varying lens sizes without issue, making them a bit more versatile for your lens selection.
Alright, so this means you should go out and buy a square filters system immediately, right? Not quite. Many photographers argue that square filters uses are obsolete in modern photography. Graduated filters are one of the main reasons to use these kits, but with modern cameras having larger dynamic ranges than ever before combined with using techniques like exposure bracketing, you can get away without using them.
On top of that, magnetic circular filters were introduced a few years ago, and they have changed everything about filter systems. Previously, if you had to screw on a circular polarizer or set up a square system, the setup time wasn't very different, so the opportunity cost to use one over the other was very little. Now, with magnetic filters, you can add a polarizer and an ND in less than 10 seconds. Factor in the size and weight difference between the two, and you're stuck wondering why you'd ever use square filters again.
The truth is most of the time, I don’t want to use filters at all if I can get away with it. If a scene does need a filter, I want it to take as little time as possible. Like many tools in photography, if it feels like it gets in my way more than it benefits me, I’ll likely just never end up using it. So, if all of this is true, why do I still own a kit?
I own a kit for the same reason people continue to shoot film photography. It slows me down, makes me more deliberate in my compositions, and connects me a bit more to the process of photography. So, when I have the time and there’s a reason to use an ND stacked with a polarizer or a graduated filter might help balance my sky, they're there. Just because modern editing and technology have made a graduated filter less important doesn’t mean I wouldn’t prefer to get the scene in one exposure. There have also been times when my circular filters caused too much vignetting and having those larger square filters was quite important.
What's Right for You?
There are a lot of options out there, and the reality is everyone's situation is different. For example, I would never suggest the square filter system I use if you didn't already have a circular polarizer that you can quickly access. If you live somewhere with a lot of waterfalls or seascape, you might need more ND options than I typically carry around. I pointed out that many photographers recommend just bracketing your exposures so you don’t have to use graduated filters anymore, but what if you aren’t comfortable with editing techniques used for blending exposures? What if you prefer to get everything in a single exposure? In those situations, graduated filters are required.
If you're just starting, all you need is a magnetic circular polarizer. They are super easy to manage and should never get in the way of your ability to create. On top of that, no matter where you find yourself in a few years, a standalone CPL will always have uses. If you do shoot scenes with water often, throw in a magnetic 6-stop ND, and you’ll cover most of your bases. Here are a few brands you can't go wrong with:
If you're looking to slow down a little and feel a little closer to the process of photography, then a filter system might be right for you. Just be aware of why you want one and what you'll use it for; otherwise, you might find yourself never taking it out of your bag.