NiSi Cine Lens Set Athena Prime RF-Mount

NiSi Cine Lens Set Athena Prime RF-Mount – Drop-In filter system and large 46mm image circle for full-frame and large-format sensors

The NiSi Athena Cine Lens Set delivers a matched family of prime lenses designed for filmmakers and videographers who need consistent optics, matched controls, and a flexible filtration system. This RF-Mount kit includes five Athena Prime lenses plus a hard case and two cine filters, providing a ready-to-shoot solution for a variety of cinematic applications.

Key optical characteristics

The Athena Prime lenses cover a focal length range from ultra-wide to portrait perspectives. They offer consistent T-stop ratings across many focal lengths, which helps maintain uniform exposure when you switch lenses during a shoot. Specifically:

• 25mm, 35mm, 40mm, 50mm and 85mm are specified as having a maximum aperture of T1.9.
• 18mm and 135mm are specified with a maximum aperture of T2.2.
• The 14mm lens has a maximum aperture of T2.4.

Additionally, the series provides an image circle of 46mm, making these lenses suitable for full-frame and even large-format sensors. The lenses emphasise fine image detail, ultra-low chromatic aberration, and micro-contrast control.

Filter and mount system

NiSi built a proprietary rear filtration system into the Athena Prime series to give filmmakers greater creative control. The design details are as follows:

• The Athena Prime series features a Drop-In filter mount for certain mounts.
• RF-, L- and G-Mount lenses include a Drop-In filter option.
• The E-Mount is available in two versions: one with Drop-In filter and one without Drop-In filter.
• The PL-mount uses a rear filter solution.

NiSi also provides a weather-sealed solution for the Drop-In filter to protect the system in variable shooting conditions.

Handling, control and compatibility

The series shares physical and mechanical attributes to improve workflow and rigging efficiency:

• All Athena Prime lenses (except the 14mm) use a 77mm front filter thread.
• Both aperture and focus rings are matched across the range to provide consistent feel when swapping lenses.
• The focus rotation on each lens is 300°, enabling precise focus pulls.
• Fluorescent focus scales are provided on the lenses and display both imperial and metric units.
• The lenses feature a standard 0.8 MOD focus and iris gear, ensuring compatibility with most follow focus and matte box systems.
• All lenses in the series are similar in weight, which reduces or eliminates the need to rebalance a gimbal when switching between Athena lenses.

Focus performance

NiSi designed the Athena Primes to minimise focus breathing. In practice, this means that changes in field of view when you adjust focus from minimum focus distance to infinity remain extremely small across the series.

Important usage notes

• Sony FX9 cameras cannot use the E-Mount version that includes Drop-In filters.
• To achieve infinity focus and obtain clear images, it is important to use the Drop-In clear filter on RF-, L-, G- and E-mounts, and to use the rear filter on PL-mount lenses.

Optional close-up/macro

NiSi offers a 77mm close-up lens that can reduce the minimum focus distance and create macro effects. This close-up lens is sold separately and attaches to compatible 77mm front filter threads (note that the 14mm does not share the 77mm thread).

What’s included in this RF-Mount kit

• 1x NiSi Athena Prime 14mm T2.4 RF-Mount
• 1x NiSi Athena Prime 25mm T1.9 RF-Mount
• 1x NiSi Athena Prime 35mm T1.9 RF-Mount
• 1x NiSi Athena Prime 50mm T1.9 RF-Mount
• 1x NiSi Athena Prime 85mm T1.9 RF-Mount
• 1x NiSi Hardcase for 6pcs NiSi Athena Lenses
• 1x NiSi Cine-filter 4x5,65" True Color Polarizer
• 1x NiSi Cine Filter 4x5,65" Black Mist 1/8

Technical specifications

FAQ

question: Which focal lengths are included in this RF-Mount kit?
Answer: This RF kit includes 14mm T2.4, 25mm T1.9, 35mm T1.9, 50mm T1.9, and 85mm T1.9, plus a hard case and two 4x5,65" cine filters.

question: Can I use Drop-In filters on all mounts?
Answer: The Drop-In filter option is available on RF-, L- and G-mount lenses. E-mount lenses are offered in two versions (with and without Drop-In). PL-mount lenses use a rear filter. Also note that the Sony FX9 cannot use the E-mount version with Drop-In filters.

question: Do I need to rebalance my gimbal when switching Athena lenses?
Answer: NiSi states that all Athena Prime lenses are similar in weight, and they do not require rebalancing on a gimbal when switching between Athena lenses, which streamlines lens changes during a shoot.

question: How do I ensure infinity focus when using the filtration system?
Answer: To achieve infinity focus and clear images you must use the Drop-In clear filter on RF-, L-, G- and E-mounts (when applicable) and the rear filter on PL-mount lenses.

question: Are the lenses weather sealed?
Answer: NiSi provides a weather-sealed option for the Drop-In filter to help protect the filtration system; the series also integrates a rear filtration approach on PL lenses.

question: What focus control and consistency features do the Athena Primes offer?
Answer: The lenses share matched aperture and focus ring feel across the range, use standard 0.8 MOD gears for compatibility with follow focus systems, have a 300° focus rotation for precise pulls, and include fluorescent focus scales in both imperial and metric units.

If you have questions about mount conversions, accessory compatibility, or need a quote for different mount options, contact us and we will source the configuration you need.