On 11 June 2024, Canon announced the RF-S3.9mm f/3.5 STM Dual Fisheye, its second lens for the EOS VR system following the RF5.2mm f/2.8L Dual Fisheye. Like its full-frame counterpart, this revolutionary new lens for APS-C EOS R system cameras consists of two fisheye lenses in one lens body, streamlining the virtual reality content production workflow by leaps and bounds. The addition of autofocus capabilities further increases its usability.
The EOS VR System: Revolutionising the 3D VR production workflow
3D VR content transports viewers into an immersive new world where you can experience a scene with greater realism than ever. It offers new, engaging possibilities for documentation, storytelling, and creative expression, and is increasingly in demand in diverse industries beyond entertainment such as tourism and education.
Advanced VR content creation is conventionally a complex process requiring high-end equipment and specialised technical skills. This is no longer the case with the EOS VR System, a solution Canon developed to make high-resolution 3D VR content production more accessible. Users can now create VR stills and videos simply by shooting with one dual fisheye lens and one camera, and then converting the images with the EOS VR Utility software.
EOS VR System: Create advanced VR content with just one lens and one camera
The EOS VR System was launched in October 2021 together with the RF5.2mm f/2.8L Dual Fisheye. It consists of:
- EOS R system cameras with advanced video capabilities
- Dual fisheye VR lenses, and
- Special software that efficiently converts image files into VR footage.
The new RF-S3.9mm f/3.5 STM Dual Fisheye is Canon’s second VR lens and its first designed for APS-C EOS R cameras. Compatible with the EOS R7 at launch, it makes the EOS VR System available to more content creators.
EOS R5 + RF5.2mm f/2.8L Dual Fisheye
Canon’s first VR lens debuted in October 2021. Its dual circular fisheye lenses achieve an overall angle of view of 190°. Designed for full-frame cameras, it is compatible with the EOS R5, EOS R5 C, and EOS R6 Mark II, and produces 8K stereoscopic 3D 180° VR footage when used with the EOS R5.
EOS R7 + RF-S3.9mm f/3.5 STM Dual Fisheye
Canon’s second dual fisheye lens, the RF-S3.9mm f/3.5 STM Dual Fisheye achieves an overall 144° angle of view. It is designed for APS-C cameras, and supports the EOS R7 at launch.
Dual fisheye lenses: reducing equipment and post-production work
Creating VR images traditionally involves capturing and stitching two images captured from slightly different points of view (“parallax images”), mimicking how human vision combines images from our left and right eye.
Before the EOS VR System, high-resolution 3D VR content production involved:
- Precisely positioning two cameras to capture parallax images
- Correcting and matching two separate sets of images from the cameras
- Stitching the images.
All that is simplified with Canon’s dual fisheye lenses’ ability to capture two parallax images simultaneously on the same image sensor.
Traditional vs. EOS VR System workflows
RF-S3.9mm f/3.5 STM Dual Fisheye: Create 3D VR content on your APS-C camera
As the second dual fisheye lens in the EOS VR System, the RF-S3.9mm f/3.5 STM Dual Fisheye contains two circular fisheye lens units that have a 3.9mm focal length, working together to achieve an easy-to-use 144° angle of view (diagonal, vertical, and horizontal angle-of-view). 144° is just enough to capture almost everything in front of you while leaving out unwanted peripheral objects such as your own feet, the tripod you’re using, gimbals, or microphones.
As it is an RF-S lens designed for EOS R series cameras with an APS-C sensor, the RF-S3.9mm f/3.5 STM Dual Fisheye is smaller and lighter than the RF5.2mm f/2.8L Dual Fisheye. This also makes it easier to move around, ideal for use on a gimbal.
The lens alone weighs around 290g. With the EOS R7, it forms a lightweight, compact combination that weighs approximately 902g (including batteries and memory card), which will be an asset for working in locations where bringing in larger gear is inconvenient or impossible.
*Cameras compatible with the RF-S3.9mm f/3.5 STM Dual Fisheye as at June 2024: EOS R7
The two fisheye lens units are around 60mm apart, roughly the same as the distance between the left and right eye on humans. This achieves parallax images that look natural to us, resulting in 3D VR images that feel more realistic.
Your workflow with the RF-S3.9mm f/3.5 STM Dual Fisheye and EOS VR Utility software
The right and left fisheye lens units in the RF-S3.9mm f/3.5 STM Dual Fisheye each project an image simultaneously onto the image sensor. For technical reasons, the image from the left lens unit is recorded on the right side of the frame, and the image from the right lens unit is recorded on the left side of the frame.
This is not the final output. When you process the footage in EOS VR Utility or with the EOS VR plug-in for Adobe Premiere Pro, the various tools will swap the position of the left and right images, convert the circular fisheye images into equirectangular images, and convert the images into a format that can be edited and viewed in a VR display platform.
High-speed, high-precision autofocus in both fisheyes
Autofocus on both fisheye lens units is driven by a gear-type lens STM (stepping motor) that moves the right and left lenses in unison. While focus tracking is not supported during video shooting, the lens supports One Shot AF—users can acquire focus through AF before shooting. This improves ease of use over the RF5.2mm f/2.8L Dual Fisheye, where only manual focusing is supported.
While the RF5.2mm f/2.8L Dual Fisheye was equipped with just a focusing ring for manual focusing, the RF-S3.9mm f/3.5 STM Dual Fisheye features an electronic focusing/control ring like other RF lenses. The control ring can be assigned to directly control other functions. It can also be used to make fine adjustments to the left-right focus difference.
Excellent optical quality
A: UD lens elements
B: ASC
Each fisheye lens unit incorporates two UD (Ultra-low Dispersion) lens elements that effectively correct aberrations, realising excellent resolution and clarity from the centre to the edges of the image.
With fisheye lenses’ extremely wide angle of view, it can be hard to leave strong light sources such as the sun out of the frame, increasing the likelihood of ghosting and flaring. This is corrected with the use of anti-reflective ASC (Air Sphere Coating) in both fisheye lens units, providing greater flexibility for even midday outdoor shoots.
Support for two types of filters
ND filters are crucial for exposure control when shooting video in bright situations. While it can’t take regular front screw-in filters due to its unique shape and structure, the RF-S3.9mm f/3.5 STM Dual Fisheye can take a 30.5mm screw-in filter in its rear. In addition, it can also take a gelatin filter (sold separately) with a specially designed rear filter holder (bundled with the lens).
RF-S3.9mm f/3.5 STM Dual Fisheye: Key specifications
Lens construction: 11 elements in 8 groups ×2
Angle of view: 144°
Closest focusing distance: 0.2m
Maximum magnification: 0.03x
No. of aperture blades: 7
Filter: Gelatin filter /Φ30.5mm screw-type filter
Size: 112 x 83.7 x 54.6mm
Weight: approx. 290g
(not including rear filter holder)
Bundled accessories
Canon Lens Cap 3.9
RF-S3.9mm f/3.5 STM Dual Fisheye Promotion Movie
RF-S3.9mm f/3.5 STM Dual Fisheye: Sample 180° VR video
This sample video was shot on the RF-S3.9mm f/3.5 STM Dual Fisheye and EOS R7, and output as a 2D 180° VR video so you don’t need 3D goggles to experience it. You can use your mouse, keyboard, or touch gestures to move around the scene, zoom in, or zoom out.
| Move around the scene | Zoom in/out | |
| Mouse | Click and drag | Use the control wheel |
| Keyboard | Arrow keys | PgUp to zoom in PgDn to zoom out |
| Mouse | Click and drag | Use the control wheel |
| Touch | Swipe | Pinch in to zoom in Pinch out to zoom out |
Note: Viewing operations might differ depending on the browser.
