NiSi Cine Lens Athena Prime 18mm T2.2 RF-Mount

NiSi Cine Lens Athena Prime 18mm T2.2 RF-Mount — 18mm wide-angle with T2.2 aperture and 46mm image circle

The NiSi Athena Prime 18mm T2.2 in RF mount is part of the Athena Cine lens series. It offers a wide-angle focal length with a maximum aperture of T2.2. The series delivers an impressive 46mm image circle, making this lens suitable for full-frame and large-format sensors.

Key features of the 18mm Athena Prime

• Maximum aperture: T2.2, as specified for the 18mm model.
• Wide-angle coverage: 18mm focal length for expansive scenes and architecture.
• Large image circle: 46mm image circle across the series, suitable for full-frame and larger sensors.
• Matched handling: Aperture and focus rings are matched across the Athena range for consistent ergonomics.
• Filter thread: Shares the 77mm front filter thread used by most Athena primes (except the 14mm).
• Focus mechanics: 300° focus rotation and fluorescent focus scales in both imperial and metric units for precise pulls.
• Gear standard: Standard 0.8 mod focus and iris gears for compatibility with follow focus and matte box systems.
• Weight consistency: Lenses in the series are similar in weight, so you typically will not need to rebalance a gimbal when switching between Athena lenses.

Filtration system and drop-in filter notes

The Athena Prime series features a proprietary rear filtration system with a Drop-In filter mount that provides flexibility for filmmakers. For RF-mount lenses, a Drop-In filter option is available.

• RF-, L- and G-Mount lenses in the Athena series offer a Drop-In filter option.
• The E-Mount will be available in two versions: with and without the Drop-In filter option.
• The PL-mount uses a rear filter instead of the Drop-In system.
• Important: Use the Drop-In clear filter on RF-, L-, G- and E-mount lenses, and the rear filter on PL-mount lenses, to achieve infinity focus and clear images.
• Sony FX9 cameras cannot use the E-Mount version with Drop-In filters.
• NiSi supplies weather sealing for the Drop-In filter to help protect the filtration system.

Compatibility and mounts

The Athena Prime series is available in multiple mounts across the range, including ARRI PL, Canon RF, Sony E, Panasonic/Leica L and Fuji G. This particular 18mm listed here is the RF-mount version, and it includes the Drop-In filter option when configured accordingly.

Use cases and accessories

Use the 18mm Athena Prime for wide-angle cinematography, landscapes, interiors and any scenario benefiting from a wide field of view and T2.2 aperture. Because the series supports a 46mm image circle and consistent ergonomics, you can switch focal lengths without significant rebalancing on gimbals.

For close-up and macro effects, NiSi offers a 77mm close-up lens (sold separately) that reduces minimum focus distance when needed.

Technical specifications

FAQ

Question: Will this 18mm RF lens cover full-frame and larger sensors?
Answer: Yes. The Athena series provides a 46mm image circle, which makes the 18mm RF suitable for full-frame and even large-format sensors.

Question: Do I need to use a Drop-In or rear filter to get accurate infinity focus?
Answer: Yes. To achieve infinity focus and clear images you must use the Drop-In clear filter on RF-, L-, G- and E-mount versions, and the rear filter on PL-mount lenses.

Question: Can I use the E-Mount version with Drop-In filters on a Sony FX9?
Answer: No. The Sony FX9 camera cannot use the E-Mount with Drop-In filters, so verify camera and mount compatibility before purchase.

Question: Are the lenses balanced for gimbal use when swapping focal lengths?
Answer: The Athena primes are similar in weight and share matched aperture and focus rings, so you generally will not need to rebalance a gimbal when switching between Athena lenses.

Question: Can I add macro capabilities to the 18mm RF lens?
Answer: Yes. NiSi offers a 77mm close-up lens (sold separately) that reduces the minimum focus distance and creates macro effects when attached.

The NiSi Athena Prime 18mm T2.2 RF-Mount combines wide-angle coverage with the series’ optical and mechanical features, making it a practical choice for filmmakers using Canon RF systems who need matched handling and large-sensor coverage.