UFL-G140 SD Underwater Semi-fisheye Conversion Lens

JAN code: 4562121437739


The UFL-G140 SD provides wild wide underwater footage nearly same view angle as using action camera on land.

Compatible camera

  • SONY FDR-X3000/X3000R
  • SONY HDR-AS300/AS300R
  • GoPro® HERO9 Black
  • GoPro® HERO8 Black
  • GoPro® HERO7 Black
  • GoPro® HERO6 Black
  • GoPro® HERO5 Black
  • GoPro® HERO+LCD
  • GoPro® HERO+
  • GoPro® HERO
  • GoPro® HERO4
  • GoPro® HERO3+
  • GoPro® HERO3

Ultra Wide Even Underwater

Though an action camera is equipped with ultra wide lens, its coverage underwater will dramatically narrow down due to different refraction ratio between air and water.
For example, maximum angle of view of GoPro® HERO7 Black is approx. 151° on land which will narrow down to approx. 94° when we put the camera in genuine dive housing and bring it underwater due to different refraction index. The INON UFL-G140 SD provides ultra wide semi-fisheye imaging with angle of view 140° underwater enabling wild underwater video work only with action cameras.

* Measured angle of view by INON or calculated angle of view underwater based on the measured angle of view. Not confirmed by camera manufacture. The measured angle of view of “HERO3+ Silver Edition” is approx. 142°(air) which is less wide than the “Black Edition”. So angle of view underwater with this lens is less than 140°. The “HERO3+ White Edition” has not been tested.


angle of view


Dynamic CFWA Imaging

Shooting through the INON UFL-G140 SD lens enables you to shoot a subject at close range to benefit deformed and/or perspective result.
The native depth of field (DoF) of the GoPro® HERO7 Black on land is approx. 60cm/2ft to ∞. With the INON UFL-G140 SD, DoF underwater will be extended to 4cm/1.6in to ∞ closer to camera side.

* DoF on land is based on focal length/aperture of camera lens and pixel pitch of the image sensor. DoF underwater is measured from "the forefront of the lens".



Professional-level Image Quality

The UFL-G140 SD is constructed of 4 elements in 4 groups. Rear element is made from high refractive index glass lens to minimize whole size dramatically without sacrificing performance. Front acrylic dome has five layers multi-coating on its inner surface providing as same grade of image quality as like optical glass dome at affordable pricing.

Professional-level Image Quality


Speedy Lens Exchange by SD Mount

Bayonet INON SD Mount compatible to support friendly and speedy lens exchange underwater. Compatible with AD Lens Holder to hold a lens when not in use.

Speedy Lens Exchange by SD Mount


Rear Replacement Lens Cap 

Front Replacement Lens Cap

Lens Hood G140

Split Easy for UFL-G140 SD

Split Easy for UFL-G140 SD

*A rubber ring to be attached on the camera side lens of the UFL-G140 SD to hold water between the lens and housing enabling to shoot a split shot by GoPro HERO9/HERO8.

Size 93.4mm / 3.7in (Diameter), 41.8mm / 1.6in (Length) (including Lens Hood)
Weight [air] 300g / 10.6oz
[underwater] approx. 153g / 5.4oz (including Lens Hood)
Mount system INON SD Mount
Depth rating 60m / 196.9ft
Body material/finishing Corrosion resistant aluminum alloy / rigid black alumite, PC etc.
Lens material/coating Optical glass/both side coating,
Optical plastic/both side hard coating, inner multi-coating
Lens construction 4 groups 4 elements
Max. view angle (*1) 140.0°(underwater)

(*1) Maximum angle of view underwater. It varies among different action cameras. 

Mfr.   Camera Depth of field with UFL-G140 SD (*2)
GoPro (*3) HERO9 Black
HERO8 Black
HERO7 Black
HERO6 Black
HERO5 Black
HERO3+ Black
4cm / 1.6in to ∞
HERO3 BLACK 10cm / 3.9in to ∞
OLYMPUS TG-Tracker 1cm / 0.4in to 80cm / 2.6ft
4cm / 1.6in to ∞

(*2) Measured DoF from foreground of the lens surface. Divide by 1.33 for visual distance underwater.
(*3) Measured distance underwater for GoPro® HERO9 Black/HERO8 Black/HERO7 Black/HERO6 Black/HERO5 Black/HEOR4/HERO3+ Black/HERO3 Black/HERO/HERO+/HERO+ LCD. Other Edition has not been tested.

[When using the UFL-G140 SD]
* The UFL-G140 SD is designed only for underwater use. When using on land, distant subject is not in focus, angle of view is not as wide as rated and vigentting is observed.

[When using for GoPro®] 
* Always set camera's Field of View (FOV) to [WIDE]/[Ultra Wide]. Using [Medium] or [Narrow] won't bring optimal performance of this lens.
* Not usable for [SuperView™] as this mode adds software-based deformation effect resulting from processing original 4:3 aspect ratio to 16:9 enhancing more aberrations when using an attachment lens. It would not recommendable to use [SuperView™] when using the UCL-G165 SD lens.
* Since this lens provides ultra wide angle of view, it is recommended to set Spot Meter to [ON] when using external lighting source (LED flashlight etc.). Setting Spot Meter to [OFF] may have washout if the external lighting device aims center of the frame.

[When using for TG-Tracker]
* Activate image stabilization function of the camera while shooting video to avoid vignetting. When taking still images, do not use attachment lens to avoid significant vignetting on image corners.
* Since the camera is designed to offer optimal focusing performance for close range subject, usable range of DoF (depth of field) with this lens is "1cm/0.4in to 80cm/2.6ft" and distant subject beyond this range gets blur.

[When using for FDR-X3000/HDR-AS300]
* Select SteadyShot (Movie) [Act] when shooting video as [Std] and [OFF] cause slight vignetting. Select SteadyShot (Still) [ON] when shooting still image. Excessive camera movement may result vignetting even SteadyShot (Movie) [Act] is selected.
* Always set camera's angle setting to [Wide]. Using [Medium] or [Narrow] won't bring optimal performance of this lens.


Compatible Accessories

AD Lens Holder for Float Arm

AD Lens Holder for Float Arm

AD Lens Holder

AD Lens Holder for Float Arm

UWL-100 Neoprene Carry Pouch

UWL-100 Neoprene Carry Pouch

Front Port Cover 100

Front Port Cover 100

Sample Movie

Sample Movie
UFL-G140 SD / UCL-G165 SD
(C)Korechika Yano
Sample Movie
(C)Takaji Ochi
Sample Movie
UFL-G140 SD / UCL-G165 SD
Carbon Telescopic Arm L
Sample Movie
Sample Movie
UFL-G140 SD comparison
HERO3+ Black
Sample Movie
UFL-G140 SD comparison
HERO4 Black
Sample Movie
(C)Mateusz Bednarcuzk
GoProHERO7 Black + UFL-G140SD
(C)Akihide Inoue
SD Selfie Set S for HERO9
(C)Akihide Inoue

360° Panorama Video

Underwater 360°panoramic movie with UFL-G140 SD by Makoto Hirose/SeaPics Japan. Six GoPro® cameras with INON UFL-G140 SD lenses are mounted on a customized mount called “rig”. The movie is created by stitching all clips by using specific editing application for 360°panoramic movie. Without INON UFL-G140 SD, it is not possible to create such a natural panoramic movie as angle of view of GoPro® camera underwater is not as wide as on land showing up seams between clips. You can move viewpoint anywhere you like by dragging your mouse over the movie.

*GOPRO, HERO, the GOPRO logo, and the GoPro Be a Hero logo are trademarks or registered trademarks of GoPro, Inc.
*Olympus, STYLUS and TG-Tracker are trademarks or registered trademarks of Olympus Imaging Corp.
*Sony and Action Cam are trademarks or registered trademarks of Sony Corporation and Sony Marketing Inc.

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