INON UWL-100 M67 wide-angle converter

uwl100 dot_bu Depth rating 60m (lens has sealed internal air-spaces).
dot_gy Achromatic afocal wide-angle converter with anti-reflection coatings front and back.
concave Magnification factor: ×0.57077
dot_gy Max. coverage: 100° UW, 158° in air (when camera lens 35mm equiv: focal length is 31.5mm). Actual coverage depends on camera and housing - see tables below.
vignet Vignetting is likely occur when camera 35mm equivalent focal length is less than 31.5mm. Zoom in to eliminate this effect.

Construction: 5 elements, 4 groups, optical glass.
Dimensions: 100mm dia., 58.5mm long.
Weight: 625g in air, 370g UW.

Test Pictures: f/8  (35mm equiv. f=35mm - Taken using Olympus C-5050)

uwl100 uwl100dt

Test Pictures: f/3.1  (35mm equiv. f=35mm - Taken using Olympus μ410)

uwl100 uwl100dt



uwl100dp Dome Port for UWL-100
dot_bu Depth rating 60m.
dot_gy Fits onto UWL-100 and forms sealed air cavity in front of lens.
cov Increases max. coverage to 131° underwater (when camera lens 35mm equiv. focal length is 31.5mm). Actual coverage depends on camera and housing - see tables below.
Materials: Optical glass dome with internal multiple anti-reflection coating. Anodised Al body.
Dimensions /mm: major diameter: 129.6. length: 48.9 dome unit only, 85.5 with UWL-100.
Weight: 498g dome unit only (air). 587g with UWL-100 underwater.

Test Pictures: f/8  (35mm equiv. f=35mm - Taken using Olympus C-5050)

uwl100_dp uwld_dt


INON UWL-100 M67 Coverage
dot_gy Angle of coverage refers to format diagonal with main camera lens focused at infinity.
dot_gy Coverage underwater with dome lens is less than coverage in air because water filling the space between the housing port and the UWL-100 rear element increases the effective focal length of the camera lens.

Camera lens Coverage with UWL-100
35mm equiv. focal length (f35) Coverage UW (α') Air UW with dome
31.5 mm 68.9° 100.5° 158.4° 131.6°
37.0 mm 60.6° 91.4° 144.9° 127.9°
37.8 mm 59.5° 90.1° 141.1° 125.0°
38.4 mm 58.8° 89.3° 139.1° 123.4°
42.9 mm 53.5° 82.9° 123.7° 111.3°

calculations based on m=0.57077 when UWL-100 rear element is immersed in water.
Coverage UW (without dome lens):
α' = 2 Arctan[ 43.266615 / (2 m f35) ]
where f35 = 35mm equiv. focal length in mm, and m (magnification) = 0.57077.

Vignetting vs focal length
Note: picture cutoff region is normally dark but has been masked in grey to make it visible.
Pictures taken using Canon S100 in ikelite housing.  Aperture = f/8. Focal lengths given are 35mm equivalent. The dome port was not fitted.

uwl100m67_24 uwl100m67_24dt


uwl100m67_28 uwl100m67_28dt


uwl100m67_35 uwl100m67_35dt


uwl100m67_50 uwl100m67_50dt

Note that chromatic aberration is worse with the S100 than it is with the C-5050 and μ410 cameras. This is because the S100 5× zoom lens forces the housing manufacturer to place the port about 25mm away from the lens entrance pupil at the wide setting. Best results will be obtained when using a fixed focal length main lens, or limited-range zoom, with the port close to the front of the lens.


Pictures by David W Knight & Steve Knight.
© Cameras Underwater Ltd. 2004, 2012.