Olympus PTWC-01 wide converter - test pictures
||Magnification: 0.6× underwater (approx).
Configuration: 4 elements, 4 groups,
Mounting: M67 screw thread.
Depth rating: 40 m (has internal air spaces).
Dimensions /mm: 130.5 Ø, 68.6 L.
Weight: 1.086 kg
Not designed to work in air.
Will block camera's internal flash (use external light source if artificial light is needed).
optical aperture: 50.8 mm - sufficient for 28 mm camera lenses if port
to entrance pupil distance is not too great (zoom in slightly or crop
image later if vignetting occurs).
Pictures taken using Canon S100 camera
in ikelite housing.
Corner detail images have been resized to 2582 × 1937 (5Mp) before cropping.
Underwater light source: 2× ikelite Pro 2800 video lights.
Lens shows slight vignetting with the S100 camera at f = 28 mm (35 mm
equiv.) but this will be pushed out of the picture if radial correction
is used. Images show exceptionally low chromatic aberration given the
relatively large port to entrance pupil distance imposed by the
5× zoom lens of the S100 camera. The excellent optical quality
can be attributed to the very large exit aperture. Pictures taken with
this adapter can be exhibited at high magnification without the need
for additional correction. Assuming a screen resolution of 96 ppi, the
corner detail images are as they would appear with the picture
displayed at 27 × 20" (68 × 51 cm).
Pictures by Steve Knight
© David W Knight & Stephen D Knight 2012, 2018