NiSi Cine Lens Athena Prime 40mm T1.9 PL-Mount

NiSi Cine Lens Athena Prime 40mm T1.9 PL-Mount — Fast T1.9 Aperture with PL Rear Filter

The NiSi Athena Prime 40mm T1.9 in PL-Mount is part of the Athena Cine Lens series and delivers the optical and mechanical traits described across the range. This 40mm prime shares the series’ matched handling, geared controls and optical design intent, including the T1.9 maximum aperture for this focal length.

Designed for consistent T-stop performance

This 40mm Athena lens has a maximum aperture of T1.9, the same as the 25mm, 35mm, 50mm and 85mm primes in the series. The series uses T-stop ratings to describe actual light transmission, which helps you maintain consistent exposure when you work across these focal lengths. For reference within the series:

• 25mm, 35mm, 40mm, 50mm & 85mm — maximum aperture T1.9
• 18mm & 135mm — maximum aperture T2.2
• 14mm — maximum aperture T2.4

Optical coverage and image quality goals

The Athena primes provide an image circle of 46mm. This image circle makes the lenses suitable for full-frame and even large-format sensors. The series is engineered to control chromatic aberration and to preserve micro-contrast, which supports finer image detail across the frame.

Mounts, filters and the PL rear-filter solution

The Athena series is available in multiple mount options. The product family offers ARRI PL, Canon RF, Sony E, Panasonic/Leica L and Fuji G mounts. The PL-mount version of the 40mm uses a rear filter rather than an external Drop-In plate.

Several mounts in the series provide a Drop-In filter mount for added flexibility. Specifically:

• RF-, L- and G-mount lenses include a Drop-In filter option.
• E-mount lenses are available in two versions: one with Drop-In filter and one without.
• PL-mount lenses utilize a rear filter.

Important operational notes supplied with the series:

• Sony FX9 cameras cannot use the E-Mount with Drop-In filters.
• To achieve infinity focus and obtain clear images, you must use the Drop-In clear filter on RF-, L-, G- and E-mounts, and use the rear filter on PL-mount lenses.

NiSi also supplies weather sealing for the Drop-In filter to protect that filter interface when conditions demand it.

Minimized focus breathing and matched mechanics

The Athena primes are designed to minimize focus breathing. In practice, this means that changes in field of view when you focus from minimum focus distance to infinity remain very small. The lenses also share matched aperture and focus ring positions across the range for predictable operation when you switch focal lengths.

All Athena primes (except the 14mm) share a 77mm front filter thread. The lenses are similar in weight across the line, so you do not need to rebalance a gimbal when you swap between Athena lenses in most cases.

Focus control and gearing for cinema use

The 40mm prime, like its siblings, provides a 300° focus rotation. It includes fluorescent focus scales marked in both imperial and metric units to support precise focus pulls in diverse shooting workflows. The focus and iris gears conform to a standard 0.8 mod, ensuring compatibility with common follow focus systems and matte box setups.

Accessories and close-up options

NiSi offers a 77mm close-up lens (sold separately) that you can use to reduce the minimum focus distance and produce macro-style effects when required. This close-up adapter matches the 77mm thread used by the series (except for the 14mm lens).

Technical specifications

FAQ

Question: Can I use this 40mm Athena lens on full-frame and large-format cameras?
Answer: Yes. The Athena series provides a 46mm image circle, making the lenses suitable for full-frame and even large-format sensors.

Question: Which mounts include the Drop-In filter option?
Answer: RF, L and G mounts come with a Drop-In filter option. E-mount lenses are available in two versions — with and without a Drop-In. The PL-mount uses a rear filter instead.

Question: Are there any limitations with the E-mount Drop-In version?
Answer: Yes. Sony FX9 cameras cannot use the E-mount with Drop-In filters, according to the series notes.

Question: Do I need to fit a specific filter to reach 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 lenses and the rear filter on PL-mount lenses.

Question: Will swapping Athena lenses affect gimbal balance?
Answer: The Athena primes are similar in weight across the series, and they do not require rebalancing on a gimbal when you switch between Athena lenses in most cases.

Question: What focus and iris gearing and marks are provided for cinema workflows?
Answer: The lenses use standard 0.8 mod focus and iris gears, offer a 300° focus throw, and include fluorescent focus scales in both imperial and metric units for precise pulling.

Question: Is there a way to get closer focus and macro effects with the 40mm lens?
Answer: NiSi provides a 77mm close-up lens (sold separately) that reduces the minimum focus distance to create macro-style effects; this accessory fits the series’ 77mm thread (except 14mm).

If you need further compatibility details or help selecting the right mount or accessories, contact us and we will source the exact configuration you require.