INON
UWL-100 M67 wide-angle converter
 |
Depth rating 60 m (lens has sealed internal air-spaces).
Achromatic afocal wide-angle converter with anti-reflection coatings
front and back.
Magnification factor: ×0.57077
 Max.
coverage: 100° UW, 158° in air (when camera lens 35mm
equiv: focal length is 31.5 mm). Actual coverage depends on camera and
housing - see tables below.
 Vignetting
is likely occur when camera 35 mm equivalent focal length is less than
31.5 mm. Zoom in to eliminate this effect. |
Construction: 5 elements, 4 groups,
optical glass.
Dimensions: 100 mm dia., 58.5 mm long.
Weight: 625 g in air, 370 g UW.
Test Pictures: f/8 (35 mm equiv. f = 35 mm - Taken using
Olympus C-5050)
Test Pictures: f/3.1 (35 mm equiv. f = 35 mm - Taken using
Olympus μ410)
 |
Dome
Port for UWL-100
Depth rating 60 m.
 Fits onto
UWL-100 and forms sealed air cavity in front of lens.
Increases max.
coverage to 131° underwater (when camera lens 35 mm equiv.
focal length is 31.5 mm). 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: 498 g dome unit only (air).
587 g with UWL-100 underwater. |
Test Pictures: f/8 (35 mm equiv. f = 35 mm - Taken using
Olympus C-5050)
INON UWL-100
M67 Coverage
Angle of coverage
refers to format diagonal with main camera lens focused at infinity.
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 |
| 35 mm
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 f
35) ]
where f
35 = 35 mm 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 35 mm equivalent. The dome port was not
fitted.
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 25 mm 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.
DWK
Radial corraction data for the UWL-100 (with and without dome adapter) are given in the
M67 adapter comparison article.
Pictures by David Knight & Steve Knight.
© David W Knight 2004, 2012, 2018.
