NiSi Cine Lens Athena Prime 50mm T1.9 PL-Mount

NiSi Cine Lens Athena Prime 50mm T1.9 – PL-Mount with rear filter

The NiSi Athena Cine Lens 50mm T1.9 in PL-Mount is part of the Athena Prime series designed for cinematographers and videographers who require consistent exposure, matched handling and strong optical performance. This 50mm model offers a maximum aperture of T1.9 and uses a rear filter in the PL version, making it suitable for professional cine workflows.

Key optical characteristics

The 50mm Athena Prime delivers a T-stop rating that reflects actual light transmission, helping you maintain consistent exposure across focal lengths. In the Athena series, the 50mm shares the T1.9 maximum aperture that delivers shallow depth of field and pleasing background separation when required.

• Maximum aperture: T1.9 (50mm)
• Image circle: 46mm — suitable for full-frame and large-format sensors
• Ultra-low chromatic aberration and improved micro-contrast for finer image detail
• Designed to minimize focus breathing so the field of view changes very little when you pull focus

Mounts, drop-in and rear filters

The Athena Prime series is available in multiple mount options, and each mount has specific filter options. For PL-Mount lenses, the series uses a rear filter. Other mounts provide Drop-In filter options as described below.

• Series mount options: ARRI PL, Canon RF, Sony E, Panasonic/Leica L and Fuji G
• PL-mount: utilizes a rear filter (this is the option for the 50mm PL model)
• RF-, L- and G-Mount lenses: have a Drop-In filter option
• E-Mount: produced in two versions — with and without Drop-In filter

Important: to achieve infinity focus and obtain clear images, use the Drop-In clear filter on RF-, L-, G- and E-mounts, and use the rear filter on PL-mount lenses. NiSi also provides weather sealing for the Drop-In filter assemblies.

Handling, gearing and consistency across the series

NiSi engineered the Athena Primes for consistent handling that simplifies lens changes on set. You can expect the following practical benefits when using the 50mm alongside other Athena lenses.

• All Athena Prime lenses are similar in weight, so you do not normally need to rebalance a gimbal when switching lenses within the series.
• All lenses except the 14mm share a 77mm front filter thread, making front-filter accessories easier to manage across the range.
• Aperture and focus rings are matched across the range for repeatable pulls and consistent ergonomics.
• Both focus and iris gears use a standard 0.8 mod, ensuring compatibility with a wide range of follow focus and matte box systems.
• The lenses feature a 300° focus rotation and fluorescent focus scales in both imperial and metric units for precise focus pulls in dim lighting.

Series focal length coverage and aperture overview

The Athena Prime family covers a wide range of focal lengths, giving you options from ultra-wide to portrait-length optics. The series focal-length and maximum aperture breakdown published for the range is as follows.

• Focal length range in the series: 14mm to 135mm (covers ultra-wide to portrait focal lengths)
• Maximum aperture overview across the series:
  • 14mm: T2.4
  • 18mm: T2.2
  • 25mm, 35mm, 40mm, 50mm, 85mm: T1.9
  • 135mm: T2.2

Accessories and optional extras

NiSi offers compatible accessories to extend the 50mm PL-Mount lens’s capabilities.

• NiSi 77mm close-up lens (sold separately) can reduce minimum focus distance and create pronounced macro effects when used with Athena lenses that accept 77mm front filters.
• Use of the correct Drop-In or rear clear filter is required to maintain infinity focus and optimal image clarity, depending on mount.

FAQ

• Question: Is the 50mm Athena Prime suitable for full-frame or large-format sensors?
  Answer: Yes. The Athena series has an image circle of 46mm, which makes the lenses suitable for full-frame and many large-format sensors.
• Question: Do I need to rebalance my gimbal when switching to the 50mm from other Athena lenses?
  Answer: Generally no. All Athena Prime lenses are similar in weight, so rebalancing is not typically necessary when you change lenses within the series.
• Question: How does the PL version handle filters compared with other mounts?
  Answer: The PL-Mount Athena lenses use a rear filter. Other mounts may offer Drop-In filter options. Always use the recommended clear filter (Drop-In or rear) to achieve infinity focus and clear images.
• Question: Can I use an E-Mount Athena with Drop-In filters on a Sony FX9 camera?
  Answer: No. The Sony FX9 camera cannot use the E-Mount version that includes Drop-In filters. Check mount compatibility before purchase.
• Question: Are the focus and aperture controls matched across the range for consistent operation?
  Answer: Yes. The Athena Primes share matched aperture and focus ring positions, and both rings use standard 0.8 mod gears for compatibility with common follow focus systems.
• Question: Can I get macro effects with the 50mm Athena Prime?
  Answer: Yes. You can use the NiSi 77mm close-up lens (sold separately) to reduce minimum focus distance and create strong macro effects on Athena lenses that accept 77mm front filters.