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Sirui 40mm T1.8 1.33x S35 AF Anamorphic Lens (FUJIFILM X, Neutral Flares)

BH #SI40AF133XXN • MFR #40AF133X-XN
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Sirui 40mm T1.8 1.33x S35 AF Anamorphic Lens (FUJIFILM X, Neutral Flares)
Key Features
  • Covers Super 35 | T1.8-T22 Aperture
  • Selectable Manual and Autofocus
  • Neutral Streak Flares
  • Creates 2.35:1 Aspect Ratio in 16:9
Capture cinematic widescreen footage with the aid of an autofocus option using the Sirui FUJIFILM X-mount 40mm T1.8 1.33x S35 AF Anamorphic Lens. This innovative prime lens uses an STM motor for fast, accurate autofocus while offering manual focus for more complicated shots handled by a camera assistant/focus puller. It produces neutral flares that are a classic feature of the anamorphic format and has a fast T1.8 maximum aperture lens that is ideal for low-light capture and for creating distinctive bokeh effects.
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Sirui 40mm T1.8 Anamorphic Overview

Manual and Autofocus Anamorphic Prime
Capture cinematic widescreen footage with the aid of an autofocus option using the Sirui FUJIFILM X-mount 40mm T1.8 1.33x S35 AF Anamorphic Lens. This innovative prime lens uses an STM motor for fast, accurate autofocus while offering manual focus for more complicated shots handled by a camera assistant/focus puller. It produces neutral flares that are a classic feature of the anamorphic format and has a fast T1.8 maximum aperture lens that is ideal for low-light capture and for creating distinctive bokeh effects.
Super 35 Coverage
  • This anamorphic prime lens has a 1.33x squeeze factor.
  • It produces a widescreen 2.35:1 aspect ratio when shooting in a 16:9 mode.
Manual and Autofocus
  • The autofocus feature now lets you capture anamorphic footage as quickly as when using spherical lenses.
  • Select manual or autofocus using the switch on the lens.
  • Use the AFL button to lock the autofocus or create a custom setting.
High Optical Performance
  • One aspherical and five cylindrical elements contribute to the high optical quality of this lens.
  • Focus breathing and chromatic aberration are well controlled.
  • Supports EXIF metadata transfer and has a USB-C port for firmware upgrading.
Ideal for Low-Light Shooting
  • The maximum T1.8 aperture enables you to capture low-light scenes using lower camera ISO settings.
  • Choose between stepped and stepless aperture settings for smooth exposure adjustments.
  • Sharpness and optical quality are maintained even in night scenes.
Flares and Distinctive Bokeh
  • Shoot with a wide-open aperture to create a distinctive hexagonal bokeh.
  • Stop down to get an oval bokeh that is typical of the anamorphic look.
  • Create notable neutral flares that can be varied using different light sources.
All Around Prime
  • This all-around 40mm lens is ideal for portraits, landscapes, street scenes, and establishing shots.
  • Horizontally equivalent to 42mm in full-frame format.
Compact Cine-Style Form
  • This prime lens features a compact, lightweight design suitable for handheld and gimbal work.
  • Cine-style features include an 80mm front outside diameter, standard 0.8 MOD gears, and wide 360° focus rotation.

Sirui 40mm T1.8 Anamorphic Specs

Key Specs
Focal Length
40mm
Maximum Aperture
T1.8
Lens Mount
FUJIFILM X
Lens Format Coverage
Super35/APS-C
Filter Thread
77 mm x 0.75
Image Stabilization
No
Electronic Communication
Yes
Maximum Aperture
T1.8
Minimum Aperture
T22
Lens Mount
FUJIFILM X
Interchangeable Mount
No
Horizontal Squeeze (Anamorphic)
1.33x
Flare Color
Neutral
Lens Format Coverage
Super35/APS-C
Image Circle
37.0 mm
Angle of View
Super 35
Horizontal: 55°
Vertical: 25.4°
Optical Design
16 Elements in 12 Groups
Filter Thread
77 mm x 0.75
Minimum Focus Distance
1.97' / 60.05 cm
Maximum Magnification Ratio
Not Specified by Manufacturer
Diaphragm Blades
11
Image Stabilization
No
Gear Standard
Focus: 0.8 MOD
Iris: 0.8 MOD
Gear Rotation
Focus: 360°
Electronic Communication
Yes
Camera Connection
10 x Flat Contacts (EXIF) Data
Diameter
Front: 3.1" / 80 mm
Length
Not Specified by Manufacturer
Weight
1.4 lb / 614 g
Packaging Info
Package Weight
3.025 lb
Box Dimensions (LxWxH)
8.5 x 6.7 x 6"

Sirui 40mm T1.8 Anamorphic Reviews

See any errors on this page?

On an APS-C camera, such as the Sony FX30, what ...

On an APS-C camera, such as the Sony FX30, what would be the equivalent focal length of this 40mm Sirui Anamorphic Lens?
Asked by: Craig
The Sirui 40 mm T1.8 1.33x S35 AF Anamorphic Lens (Sony E, Neutral Flares) would have a 60 mm view on the APS-C sensor of the Sony FX30.
Answered by: Chris H
Date published: 2025-03-07

The angle of view specs for the MFT version are ...

The angle of view specs for the MFT version are the same as the E-mount version. Is the MFT crop factor taken into account here?
Asked by: David
When using the Sirui 40mm T1.8 1.33x S35 AF Anamorphic Lens (Micro Four Thirds, Neutral Flares) and all other lenses, the focal length of a lens does not change when used on a different system; it is the field of view compared to a full frame that changes. Crop factor compared to 35mm equivalent is only relevant when comparing to full frame.
Answered by: Elliot
Date published: 2025-03-10
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