Seconding the fixed ND advice above — GM coatings are unforgiving, cheap glass gets flare-y fast. For safety/consistency I’ve had solid results with:
- B+W XS-Pro Digital ND MRC nano 67mm (6-stop) / B+W XS-Pro Digital ND MRC nano 77mm (6-stop)
- Hoya HD3 ND64 77mm (6-stop)
- If you must go variable: PolarPro Peter McKinnon Variable ND 2-5 Stop 77mm (use mid-range, avoid max to dodge weirdness). Step-up ring to 82mm helps 24mm vignetting.

> “cheap NDs cause a color shift and extra flare… video… without vignetting at the wide end”

Yo, been there. For GM glass I’ve had the least drama with fixed NDs: Breakthrough Photography X4 Neutral Density 6-Stop ND Filter and Breakthrough Photography X4 Neutral Density 3-Stop ND Filter (clean color, solid flare control). If you really need variable, PolarPro Peter McKinnon Variable ND Filter II 2-5 Stop is the one I’d trust… not cheap, but no “X” unless you push it. Buy one big size (82mm) + step-up rings = save $$.

Just catching up—pro tip: use filter size charts on B&H / LensRentals so you can standardize with step‑up rings (no wide-end vignette). For GM glass, I’d look at NiSi ND-VARIO 1-5 Stops (TRUE COLOR) 82mm for video (less color shift), or fixed cinema-style like Tiffen IRND 0.9 (3-Stop) 82mm + Tiffen IRND 1.8 (6-Stop) 82mm. Also check Gerald Undone’s ND tests on YouTube… super nerdy but useful lol. cheers

- In my experience, yeah 100%—cheap NDs love to go green/magenta and flare like crazy on GM glass, same.
- I’d stick to high-end fixed NDs for clean color + less ghosting, and only use a variable ND if it’s a really good one (otherwise you get the “X” pattern + wide-end weirdness).
- Tiny thing that helped me: slim rings + step-up (to the larger thread) reduces vignetting on 24mm and keeps the mattebox vibes for video.

Helpful thread 👍

Facts.