Disclosure: Some links in this article are affiliate links. We may earn a commission on qualifying purchases at no extra cost to you.
The number that determines which ND filter fits your lens has nothing to do with your focal length. A 50mm lens can take a 49mm filter, a 52mm filter, or a 77mm filter depending on which 50mm you own — because the number that matters is the thread diameter printed on the lens barrel, marked with a small "Ø" symbol, usually stamped under the lens cap or around the front rim. Confuse the two and you'll order a filter that clicks against the barrel and threads onto nothing.
This guide runs through every common thread size from 49mm up to 95mm, tells you which lenses typically carry each size, and gives you a fixed and a variable ND pick for the ones worth stocking. It also covers the one trick that saves most photographers from buying six different filter sizes: the step-up ring.
Two filter families show up throughout: fixed ND filters, which are a single piece of coated glass at one specific density, and variable ND filters, which stack two polarizing elements to let you dial density up or down on the fly. They solve different problems, and picking the wrong one for your use case is the most common mistake in this category — covered in detail below.
This guide focuses on thread-mount circular filters for stills and video work with mirrorless and DSLR lenses. If you shoot with a matte box or clip-in system, the sizing logic differs.
As an Amazon Associate, PhotoGearHQ earns from qualifying purchases.
Quick Reference: Size, Stops, and Type
| Thread size | Typical lenses | Best filter type |
|---|---|---|
| 49mm / 52mm | Compact primes, 50mm f/1.8, older Nikkor primes | Fixed ND64/ND1000 |
| 58mm | Classic 18-55mm kit zooms, 50mm f/1.8 STM | Fixed or budget variable |
| 62mm / 67mm | APS-C mid-zooms, mirrorless standard zooms | Fixed ND1000 or variable 1-9 stop |
| 72mm / 77mm | f/2.8 pro zooms (24-70, 70-200) | Fixed premium ND or hard-stop variable |
| 82mm | Fast wide zooms (f/2.8 14-24, f/1.2 primes) | Hard-stop variable or premium fixed |
| 95mm | Super-telephoto zooms (200-600 class) | Variable ND, 1-8 stop range |
How to Find Your Lens's True Filter Size
Look at the front of the lens barrel, either printed directly on the rim or stamped just inside where the lens cap snaps on. It reads as "Ø" followed by a number in millimeters — Ø58, Ø77, Ø82. That number is the filter thread diameter, and it's the only number you need.
Two things drive that number, and neither is focal length. The first is sensor coverage: a lens has to project a wide enough image circle to cover the sensor, which relates more to focal range and design than to the number printed on the barrel. The second, more reliable predictor, is aperture. A 50mm f/1.8 lens has a modest front element and typically takes a 49mm or 52mm filter. A 50mm f/1.2 needs to gather far more light and often demands 77mm or 82mm. The faster the maximum aperture, the larger the front element usually needs to be, and the bigger the filter thread.
Common sizes cluster at 49, 52, 55, 58, 62, 67, 72, 77, 82, and 95mm. If two lenses in your bag share a thread size, they can share filters — worth checking before you buy per lens.
Fixed vs. Variable ND: Which Type Fits Your Need
A fixed ND filter is a single piece of glass at one specific density — ND8 (3 stops), ND64 (6 stops), or ND1000 (10 stops) are the common steps. It's optically simpler than a variable filter, which means less risk of color cast or artifacts, and it's usually the cheaper way to buy a specific density. The tradeoff is that you need multiple filters to cover different lighting conditions, and you have to compose and focus before screwing it on, since a 10-stop filter is close to opaque.
A variable ND filter stacks two rotating polarizing elements, letting you dial the density anywhere within a range — commonly ND2 to ND400 (1 to 9 stops) on budget models, or a narrower 1-5 or 2-5 stop range on premium ones. This convenience comes at a cost: rotating a variable ND toward its darkest setting on a wide-angle lens can produce an "X" pattern — a visible dark cross or banding caused by the two polarizers interacting — along with a mild color shift. Premium variable filters built with hard mechanical stops (NiSi True Color, PolarPro's Peter McKinnon line) limit the rotation range specifically to avoid the X-pattern, trading total range for cleaner results.
The practical split: stills and long-exposure landscape work favor fixed ND64 or ND1000 filters for the cleanest image. Video work, where the shutter speed is effectively locked to your frame rate (24fps at a 180° shutter angle means roughly 1/50s), favors a variable ND you can adjust as the light changes through the day — ideally one with hard stops.
49mm and 52mm — Compact Primes and Kit-Lens Naturals
These sizes show up on compact primes, older Nikkor lenses, and the "nifty fifty" class — the Nikon 50mm f/1.8 is a common 52mm example, alongside several Micro Four Thirds primes and older Canon EF wide primes.
K&F Concept 67mm ND1000 line (fixed, also sold down to 37mm): Japanese AGC optical glass with 28-layer multicoating rated at 0.2% reflectivity, an ultra-slim aluminum-alloy frame, and a hydrophobic waterproof coating. The line runs across sizes including 49mm and 52mm.
Check Price on Amazon
Verdict: a clean, no-compromise 10-stop fixed ND for stills at the smaller end of the thread range. Perfect for landscape and long-exposure shooters using compact primes.
At these sizes, skip variable ND filters unless you already own the step-up rings to run a larger one instead — small-thread variable NDs are more prone to vignetting and color cast because the glass elements have less room to work with.
58mm — The Classic Kit Zoom Size
58mm is the filter thread on the Canon and Nikon 18-55mm kit zooms that ship with entry DSLRs, as well as the Canon EF 50mm f/1.8 STM.
Neewer 58mm Variable ND2-400 (1-9 stops): MRC multicoated optical glass, water- and scratch-resistant coating.
Check Price on Amazon
Verdict: a serviceable budget variable ND for casual video on a kit lens. Expect visible color cast and the X-pattern risk at the darkest end of its range — stay a stop or two below maximum.
Perfect for: beginners shooting occasional handheld video who don't want to invest in a hard-stop filter yet.
62mm and 67mm — Enthusiast Mid-Zooms
67mm is one of the most common enthusiast sizes — it covers APS-C mid-range zooms like the Sony 16-55mm and Tamron 17-70mm, along with the Sony FE 16mm f/1.8. 62mm covers adjacent primes and macro lenses in similar price tiers.
K&F Concept 67mm ND1000 (fixed, 10-stop):
Specs: Japanese AGC glass, 28-layer multicoating, 0.2% reflectivity, aluminum-alloy frame.
Check Price on Amazon
Verdict: the default long-exposure pick at this size — clean color, minimal reflectivity, easy to source in every thread diameter you'll need.
K&F Concept 67mm Variable ND2-400 (B-Series, 1-9 stops):
Specs: AGC optical glass, 18-layer coating, 7.4mm slim frame, continuous 360° rotation with no hard stops.
Check Price on Amazon
Cons: no hard stops, so over-rotating into the darkest range risks the X-pattern; the manufacturer itself doesn't recommend it below 35mm focal lengths. It also requires an oversized 72mm lens cap.
Verdict: a genuinely useful all-in-one for video at this size, as long as you keep it out of its extreme range.
Urth ND1000 Plus+ (fixed, 67mm, also sold 37-112mm):
Specs: German Schott B270 optical glass, 20-layer nano-coating, magnalium rim, double-threaded for stacking, waterproof and oil-proof.
Check Price on Amazon
Verdict: a step up in glass quality over budget fixed NDs, with a slim rim that avoids added vignetting even on wider mid-zooms. Note that white-balance shift varies slightly by camera body — a quick custom white balance corrects it.
72mm and 77mm — The Pro-Zoom Standard
77mm is the standard front thread on professional f/2.8 zooms — the Canon 24-70mm f/2.8, 24-105mm f/4, 70-200mm f/2.8, and Canon RF 100-500mm all use it, as do most Nikon f/2.8 zoom equivalents. 72mm covers some Canon primes in the same tier, including older 24mm f/1.4 and 85mm f/1.2 designs.
Hoya PROND1000 / PRO ND-EX (fixed, 77mm, sold 49-82mm):
Specs: optical glass, matte-black anodized aluminum frame, ACCU-ND coating on both front and back surfaces designed for color-neutral transmission across densities, including into the infrared range.
Check Price on Amazon
Verdict: independent transmission testing has placed ACCU-ND coatings among the most color-neutral fixed NDs available, with only a small measurable red cast and no visible IR pollution. A strong choice for landscape shooters who don't want to correct color in post.
Breakthrough Photography X4 ND (fixed, 77mm; also 3/6/10/15-stop):
Specs: Schott Superwhite B270 optical glass, CNC-machined brass traction frame, 16-layer MRC coating plus a nano top coat, weather-sealed.
Check Price on Amazon
Verdict: independent side-by-side testing against a previous benchmark 10-stop filter found the X4 sharper and more color-neutral, with an average measured transmission of 0.108% across visible and infrared light — close to the theoretical optimum for a 10-stop density. The brass frame is genuinely more resistant to cross-threading than aluminum, though it costs accordingly.
Perfect for: long-exposure landscape and architecture work where color accuracy in a single shot matters more than versatility.
82mm — Fast Wide-Angle and f/1.2 Territory
82mm covers the newest generation of fast wide zooms — Canon RF 15-35mm f/2.8, RF 24-70mm f/2.8, Sigma 14-24mm f/2.8 — plus most 50mm f/1.2 primes. It's also the size worth standardizing on if you're buying step-up rings (see below).
NiSi True Color ND-VARIO Pro Nano (82mm, 1-5 stops):
Specs: high-definition optical glass, aluminum frame, NiSi Nano waterproof coating, hard mechanical stops at both ends of its 1-5 stop range.
Check Price on Amazon
Verdict: the hard stops are a deliberate design choice to eliminate the X-pattern entirely by limiting rotation to a safe range, and the "True Color" coating measurably minimizes color shift versus open-range variable NDs.
Cons: 1-5 stops won't get you to full darkness on a bright midday shot — pair with a fixed ND1000 for extreme long exposures.
PolarPro Peter McKinnon Signature Edition II (82mm, 2-5 stop, separate 6-9 stop model available):
Specs: fused quartz glass, 16-layer anti-reflection coating, aluminum frame, hard stops, includes a protective cover and magnetic hard case.
Check Price on Amazon
Verdict: fused quartz is a genuine step up in clarity over standard optical glass, and the hard-stop design keeps the X-pattern out of the frame. This filter stands out in independent gear roundups for build quality and attention to detail rather than any single spec.
Perfect for: hybrid shooters who want one variable ND clean enough for both stills and video, and are willing to pay for it.
Freewell Versatile Magnetic Variable ND System (82mm base, modular):
Specs: CNC metal frame with magnetic mount, 18-layer multicoated glass, separate swappable VND2-5 and VND6-9 elements.
Check Price on Amazon
Cons: no front threads once mounted, so it's incompatible with a matte box; hard stops only exist at the extreme ends of each module, not throughout.
Verdict: the fastest way to swap ND strength on a run-and-gun video shoot, at the cost of losing standard filter-stacking compatibility.
95mm — Super-Telephoto and Cinema Glass
95mm is a different category of buyer entirely: super-telephoto zoom owners. The Sony FE 200-600mm f/5.6-6.3 G OSS carries a confirmed 95mm filter thread, as does the Sigma 150-600mm and Nikon 180-600mm class of lenses, plus a range of large cinema lenses. None of these lenses accept drop-in filters, so a front-thread ND is the only option — and at this diameter, filters get noticeably more expensive per unit.
The good news: the X-pattern problem that plagues variable NDs on wide lenses is far less relevant here, since it's primarily a wide-angle artifact. A variable ND is a genuinely good fit at 95mm.
Urth Variable ND2-400 (95mm, roughly 1-8.6 stops):
Specs: Schott B270 glass, 20-layer multicoating plus a protective nanocoating, slim double-threaded ring for stacking.
Check Price on Amazon
Verdict: a wide adjustable range in a size where buying multiple fixed densities gets expensive fast. Well suited to wildlife and telephoto video shooters who need to react to changing light without swapping glass mid-shoot.
NiSi True Color ND-VARIO Pro Nano (95mm, hard-stop 1-5 stop range):
Specs: high-definition optical glass, aluminum frame, hard mechanical stops, front thread larger than the rear to reduce vignetting risk when stacking.
Check Price on Amazon
Verdict: if color accuracy matters more than covering the full darkness range, this is the cleaner option — the tradeoff is a narrower usable range than the Urth.
Step-Up Rings: Buy Once at Your Largest Thread
If your lenses span several thread sizes, the standard workaround is to buy your best filter — usually the fixed ND1000 or the hard-stop variable — at your largest lens thread, typically 77mm or 82mm, and adapt it down to smaller lenses with a step-up ring.
Step-up rings work in one direction reliably: mounting a larger filter on a smaller lens thread (a 67mm lens with a 67-to-82mm ring) rarely causes vignetting, because the larger glass sits close to the lens. Going the other way — a step-down ring putting a small filter on a large lens — pushes the glass further from the lens and vignettes far more often. Stick to step-up only.
Single-step rings (67mm directly to 82mm) outperform stacked rings (67mm to 77mm to 82mm) for the same reason: less total distance between glass and lens, less risk of corner shading. Thin, brass or anodized-aluminum rings minimize this further.
K&F Concept Step-Up Ring Set: CNC-machined brass or anodized aluminum, sold as single rings or as 9-to-11-piece kits spanning 49mm through 82mm.
Check Price on Amazon
Verdict: the cheapest way to consolidate a filter collection down to one or two premium pieces instead of buying a fixed and variable ND at every thread size you own.
Two caveats worth knowing before committing to this route: a step-up ring moves your camera lens hood incompatible with that lens, since the ring extends past where the hood normally seats. And on ultra-wide lenses (16-24mm and wider), even a well-chosen step-up ring can introduce mechanical vignetting that a same-size slim filter would avoid — at those focal lengths, buy the correctly sized filter directly rather than stepping up.
Which ND Filter Should You Buy?
Shooting long exposures on a tripod, still photography only: a fixed ND64 or ND1000 in your lens's native thread size. Fixed glass avoids the color cast and X-pattern risk entirely, and it's the cheaper way to buy a specific stop count.
Shooting run-and-gun video with changing light through the day: a hard-stop variable ND (NiSi True Color or PolarPro Peter McKinnon) in the 1-5 or 2-5 stop range. The narrower range costs you some flexibility but keeps the image clean.
Shooting on an ultra-wide lens (24mm or wider): avoid open-range variable NDs regardless of budget — the X-pattern shows up fastest on wide glass. A fixed ND or a hard-stop variable kept well below its maximum density is the safer route.
Own several lenses in different thread sizes: buy once at 82mm (or your largest thread) and use single-step, thin step-up rings for everything smaller. Skip this approach entirely for anything wider than 24mm.
Shooting a super-telephoto (200mm+ zoom, 95mm thread): a variable ND is the practical choice here since the X-pattern risk is low on telephoto glass, and buying multiple fixed densities at 95mm gets expensive fast.
Frequently Asked Questions
Q: Does filter size depend on my lens's focal length?
No. Filter size is the thread diameter on the lens barrel, marked with a "Ø" symbol, and it's driven mainly by aperture and lens design, not focal length. Two lenses at the same focal length can take completely different filter sizes depending on their maximum aperture.
Q: Can I use a smaller filter on a larger lens with an adapter?
Not recommended. Step-down rings (small filter, large lens) push the glass away from the lens and frequently cause vignetting. Step-up rings, which mount a larger filter on a smaller lens, are the direction that actually works.
Q: Why does my variable ND filter show a dark X across the frame?
That's the X-pattern, a cross-polarization artifact that happens when a variable ND's two internal polarizing elements are rotated too close to their darkest setting, especially on wide-angle lenses. Filters with hard mechanical stops limit the rotation range specifically to prevent this; on open-range variable filters, staying a stop or two below maximum avoids it.
Q: Do I need a slim filter mount?
Only if you're shooting wide-angle (24mm or wider) or stacking multiple filters. On standard and telephoto lenses, a normal-thickness filter frame rarely causes visible vignetting.
Q: Is a 10-stop or a variable ND better for daytime video?
Variable, in most cases. Video shutter speed is locked to your frame rate, so the amount of light you need to cut changes throughout the day as the sun moves — a fixed 10-stop filter is often too dark in the early morning and exactly right at noon. A variable ND with a 2-6 stop range covers that swing without a filter change.
Conclusion
The confusion between filter size and focal length is the single most common reason people buy the wrong ND filter — the fix is simply reading the Ø number under your lens cap before shopping. From there, the decision comes down to two questions: what thread size does that number point to, and does your shooting call for the color accuracy of a fixed ND or the flexibility of a variable one.
For single-lens shooters, buying the right fixed or hard-stop variable filter in your exact thread size is the simplest path. For anyone juggling multiple lenses across several thread sizes, a single premium filter at 82mm paired with single-step brass step-up rings covers nearly everything except true ultra-wide glass, where a native-size slim filter still wins. Pair either approach with a best-of ND filter roundup if you want side-by-side picks across brands, and check our travel tripod guide if long exposures are the reason you're buying an ND in the first place.
