Can Budget Filters Handle the 102MP GFX100S – and One Very Wet Nikon?

This field review explores whether budget-friendly magnetic filters from K&F Concept can deliver professional results, even when paired with the ultra-high-resolution Fujifilm GFX100S. Tested in harsh coastal conditions alongside a weather-beaten Nikon Z50, the filters performed surprisingly well—retaining sharpness, colour accuracy, and ease of use. The magnetic system allowed for quick changes in the field, and while there were minor usability concerns in high winds, overall performance exceeded expectations. A practical, affordable option for landscape photographers who shoot on location.

Testing gear in a studio can tell you a lot—but using it on location tells you far more. On a windswept South Devon beach, I recently put a set of budget-friendly magnetic filters from K&F Concept to the test. This wasn’t a pixel-peeping lab review. It was a genuine field experiment involving strong light, shifting skies, and less-than-ideal conditions for photography.

My aim was simple: to see how these budget filters held up when used on a high-resolution medium format camera—the Fujifilm GFX100S. The Nikon Z50 came along too, used for filming behind-the-scenes footage. Unfortunately, it also took an unexpected dip in a rockpool.

The question I set out to answer: can affordable filters genuinely deliver when paired with serious photographic equipment?

Field Testing: Not a Fair Weather Scenario

The day began with strong coastal winds and scattered clouds, the kind of conditions that test not just camera gear but also patience and preparation. I chose the location precisely because it offered contrast, movement, and unpredictability—an ideal mix for evaluating filter performance, particularly when dealing with flare, reflections, and general usability.

K&F Concept had sent through an 82mm magnetic filter kit, which included 3-stop (ND8), 6-stop (ND64), and 10-stop (ND1000) neutral density filters, as well as a graduated ND. The kit also included a magnetic adapter ring to fit the filter thread of the lens. In addition to this review kit, I brought along some of my own K&F accessories—a magnetic 82mm circular polariser and an 82mm magnetic lens cap.

The filters snap on and off magnetically—a simple feature, but one that makes a noticeable difference when working outdoors in less-than-ideal conditions. There’s no need to screw or unscrew each filter manually, which means fewer missed moments and less risk of cross-threading in the cold.

First Impressions and Build Quality

The build quality felt surprisingly solid for the price point. The filters themselves are lightweight, with clear labelling and a reassuring click when placed on the magnetic base. The circular polariser in particular impressed me straight out of the box. There’s a sense of thoughtful design—not luxury-grade engineering, but a practical, durable solution for photographers who want to work quickly and travel light.

Although I had the Nikon Z50 with me, it was used exclusively for filming, not for filter testing. Sadly, it took an unscheduled plunge into a rockpool during the shoot. Sadly, it didn’t make it—rest in peace, Z50.

The Circular Polariser: Optical Performance in Harsh Light

The circular polariser handled the harsh coastal light well, cutting reflections off the wet sand and darkening the sky with a natural, controlled effect. There was no visible colour cast, which can sometimes be an issue with budget filters. Colours remained true, contrast improved, and I didn’t detect any significant softening—even when zooming in during post-production.

This particular polariser would be a useful tool even without the magnetic convenience, but the speed of filter changes and the inclusion of a magnetic lens cap make it especially appealing for location work. The secure fit and ease of use made it a genuinely helpful part of the kit.

The GFX100S and ND Filters: Budget Meets Medium Format

Switching to the Fujifilm GFX100S presented a different kind of challenge. With over 100 megapixels of resolution, this camera will expose even the smallest flaw in optics, alignment, or coatings. If a filter isn’t optically up to the task, it will show—whether in edge softness, vignetting, or colour distortion.

Using the 82mm ND filters on a wide lens, I tested the 3-stop, 6-stop, and 10-stop filters for longer exposures. Even with waves rolling in and shifting light across the landscape, the filters performed impressively well. Sharpness held across the frame, and although there was a very slight warming of the image with the ND64 and ND1000, it was subtle and easily corrected in post.

There was no evidence of colour shift toward green or magenta—something that can plague cheaper ND filters, particularly in strong light. Nor was there any loss of micro-contrast or noticeable ghosting.

Real-World Usability: The Benefit of Magnetic Design

Beyond image quality, there’s a practical reason to appreciate magnetic filters—speed. On location, conditions change quickly. Light can go from harsh to flat in seconds, especially on the coast. With a traditional screw-in system, switching from an ND to a polariser means pulling the camera down, unscrewing one filter, and screwing on another—all while watching your composition vanish.

With this system, I could switch filters mid-shot, keep the camera stable on the tripod, and react quickly to changes in light or tide. The magnetic lens cap also allowed me to protect the filter while walking between compositions without needing to remove anything. This was particularly useful when moving quickly between dry sand and wet rocks.

Limitations and Considerations

No filter system is perfect. In high winds, the magnetic caps are slightly vulnerable—they can come off if knocked or caught by a strong gust. The included filter pouch, while functional, isn’t the most intuitive to use. A flat, fold-out wallet might be a more field-friendly solution.

One other point to note: stacking filters, while technically possible, does add height to the lens, and ultra-wide users may notice minor vignetting depending on lens choice and framing.

That said, these are relatively minor concerns for a filter system in this price range. The optical quality remained consistent, and usability was, on the whole, excellent.

Final Verdict: Impressive Value, Especially for Outdoor Work

Budget filters often carry a reputation for compromise. But in this case, K&F Concept has produced a set of tools that are genuinely useful for landscape photography—even on a camera as demanding as the GFX100S. The magnetic system speeds up workflow, the image quality is more than acceptable for most uses, and the filters themselves are lightweight, durable, and surprisingly well constructed.

Would I use them for critical commercial jobs where every detail matters? Possibly not. But for personal projects, YouTube videos, or casual fieldwork where conditions are unpredictable, they perform more than adequately. In fact, they performed well enough that I wouldn’t hesitate to use them again on location—particularly when weight, speed, or simplicity is a priority.

Concluding Thoughts

It’s easy to assume that premium cameras require premium accessories across the board. And while there’s some truth to that—cheap glass can undermine expensive gear—it’s not always the case. When it comes to filters, there’s a growing middle ground of products that combine practical design with respectable performance at a fraction of the cost of premium options.

This test proved that even with high-resolution sensors and coastal conditions working against them, well-made budget filters can absolutely deliver. For photographers who value efficiency, flexibility, and outdoor usability, the K&F Concept magnetic filter system is worth serious consideration.