Olympus C-8080 Camera,
Underwater
Housings, Ports and Wide-Angle Lens.
 |
Olympus PT-023
 40m |
|
|
 PT-023
housing
PPO-05 port
Ikelite housing
Dome port
Comparison
Olympus
C-8080 Wide Zoom Camera:
|
Olympus software and RAW files:
Advanced users will probably prefer to use the Olympus RAW import
Photoshop-plugin available from Olympus' website. C-8080 owners
must otherwise use the 'RAW development' feature of the supplied
Olympus Camedia Master 4.2 software. The Olympus software falls
somewhat short of what can be achieved by adjusting 48bit data
in Photoshop, particularly because it lacks a histogram display
and allows only stepwise adjustment of contrast and colour balance,
but images can be adjusted so that they are good enough to allow
final adjustment of the 24bit output files in Photoshop without
significant loss in quality. The best saving option after adjustment
in the Olympus software is 24bit uncompressed TIFF; and for those
who wish to file their pictures sensibly, the files produced
must be rescued from C:\Documents and Settings\All
Users\Application Data\OLYMPUS\Camedia Master 4\Album\Samples\[album_name]
(on the author's computer at least - use the Windows Explorer
search utility if you can't find 'em). After retrieving the image
files you can use Photoshop to give final tweaks and re-save
them with LZW compression and thumbnails. Note that in some cases,
it may be necessary to log on as administrator to locate the
Album folders and enable user-access.
One of the annoying features of the Olympus software is that
it does not allow users to decide where image files will be saved,
and insists on putting them on the C: drive under 'Application
Data' (see above). If you have a fairly small disk drive, and
you save your files as uncompressed TIFFs at full camera resolution
(23.4MB), you will quickly fill up your boot partition and run
out of virtual memory. Fortunately however, Camedia Master does
not use its own database, it just uses the normal file system;
which means that it is possible (using Windows Explorer) to cut
files from an Album folder and paste them elswhere, or even paste
files into an Album folder provided that they are of a type that
Camedia Master can understand, and the software will simply list
and work on what is there. Note incidentally, that instead of
having to pay for an upgrade so that you can indulge in such
rare and specialised activities as 'e-mailing pictures to other
people', you can simply cut or copy pictures from the Album folders
and deal with them in the normal way. Note also, that if you
do decide to let Camedia Master manage your image files, you
must edit your backup routines to point at its Album folders.
Note: If you are running Windows 2000, and you have previously
installed software for other Olympus cameras, you may discover
on connecting the camera to the USB port that the computer cannot
detect the camera or gives an error message saying that a driver
is unavailable. In this case you may need to install Microsoft
update 822831:
support.microsoft.com/default.aspx?scid=kb;en-us;822831&Product=win2000
then remove and reinstall the camera software.
 Memory card
corruption:
The author has experienced, and others have reported, that the
C8080 and C5060 cameras sometimes corrupt the file system on
CF cards which have been formatted at the factory or by a non-Olympus
camera. The solution to this problem is to format the card in
the Olympus camera before using it. |
Olympus
PT-023 Housing
for C-8080wz
Materials: clear polycarbonate
housing, red polycarbonate control knobs, Ni-plated brass control
shafts, Fluorite tempered glass lens port, Anodised Al lens ring
& sync connector cap, Stainless steel buckles, Silicone main
O-ring, NBR LCD hood.
Dimensions /mm: 181w, 188h,
200d. Weight: 1475g , excluding
LCD hood, lens cap & strap.
Kit includes: Wrist lanyard,
grease, Silica gel, O-ring remover, ballast weight, LCD hood,
lens cap, sync connector cap. |
 |
|
Bulkhead flash connector:
The metal version
of the Olympus flash connector requires maintenance even if an
external flash system is never used. Remove the cap or plug frequently
and apply silicone grease to the screw thread before reassembly.
Failure to carry out this procedure may result in seizure of
the screw thread due to salt water corrosion. Attempting to remove
the connector blanking cap or sync-cable plug by force will rip
the bulkhead connector from the housing and may cause irreparable
damage. |
 |
Olympus PT-023 Housing
and C-8080 Camera
Test Pictures using Standard
Port
Internal Flash:
Standard Port, Full Wide, ISO 50, aperture as indicated. |
|
The Diffuser-box of the PT-023 housing gives the best internal-flash
underwater performance (flatness of illumination) seen by the
author to date. The light-trap design is good and there are no
signs of light leakage into the port. Note however, that the
flash output is very low, and the pictures above were taken at
close range in perfectly clear water. In conditions of moderate
visibility, backscatter is likely to be a problem, and an external
flash unit is (as always) strongly recommended. |
External flash, corner detail vs aperture:
Standard Port, Full Wide, ISO 50, Ikelite DS-125 flash with 4100.5
TTL slave sensor, aperture as indicated. Corner detail image
is full size (same resolution as original). |
Radial Correction (removal of pincushion distortion and
chromatic aberration):
Same photograph as immediately above, corrected using Panorama
Tools (see the software
optical correction article for an explanation of the method). |
|
PanoTools
Radial Correction
Coefficients |
 |
The chromatic aberration visible in the uncorrected pictures
is almost entirely due to the air-water boundary and is unavoidable
when using a lens with 75° coverage behind a flat port. The
effect will be reduced at longer focal length settings of the
zoom lens.
Radial correction allows complete elimination of chromatic aberration
and pincushion distortion. This will be beneficial if large prints
are required, but is not essential for small album photographs. |
PPO-05
Wide Port and WCON-08D Conversion Lens
PPO-05 Wide Port:
For use with CLA-8 bayonet adapter and WCON-08D wide converter
lens.
Depth Rating:
40m.  Double
O-ring seals.
 Underwater photographs
will exhibit noticeable optical distortion (but pictures taken
in air are not affected). Software optical correction is recommended.
See test pictures for details.
Materials: Fluorite tempered
glass optical port with anti-reflection coating. Clear polycarbonate
body, Silicone O-rings, Other parts: ABS, NBR, red polycarbonate.
Dimensions: Max dia 156mm,
overall length 90mm. Weight:
600g, excluding lens cap.
Supplied accessory: Grease,
O-ring remover, lens cap.
WCON-08D Converter Lens:
 Magnification:
0.8x.
Coverage at full wide in air: 88° (35mm equiv: 22.4mm) |
Optical Data*
Lens System
(zoom setting = full wide) |
35mm equiv.
focal length |
Coverage
in air |
Coverage UW
(flat port) |
|
Standard lens. |
28mm |
75° |
54° |
|
Std. lens + WCON-08D |
22.4mm |
88° |
62.5° |
|
* Angle of coverage
figures are nominal, i.e., on picture diagonal when lens is focused
at infinity. |
|
PPO-05 Wide Port and WCON-08D
Lens
Test Pictures
Distance, camera to test card: 3m. Zoom setting:
Full wide. Aperture: f/5.6. ISO: 50.
Light source: Mixed daylight and Ikelite DS-125 with 4100.5
slave sensor.
(The white measuring stick attached to the bottom of the test
card is 1m long). |
Close-up, corner detail vs aperture:
PPO-05 wide port, WCON-08 wide lens, Full wide, ISO 50, Ikelite
DS-125 with 4100.5 slave sensor, aperture as indicated. |
Radial Correction (removal of pincushion distortion and
chromatic aberration):
Same photograph as immediately above, corrected using Panorama
Tools (see the software
optical correction article for details of the method). |
|
PanoTools
Radial Correction
Coefficients:
|
 |
|
The addition of the wide conversion lens gives the C-8080 an
effective 35mm equivalent minimum focal length of 22.4mm. This
gives a nominal angle of coverage of 88° in air and 62.5°
underwater. The use of such a wide angle lens behind a flat port
underwater results in a degree of pincushion distortion and chromatic
aberration which will be noticeable even in small album prints.
Hence, for underwater photography, software optical correction
is strongly recommended. Correction will not be needed if the
port is used merely for water protection, e.g., for surface water-sports
photography. |
Ikelite
Housing for Olympus C-8080
 |
 Flash interface
circuitry built into the housing allows TTL exposure control
via the hot-shoe with Ikelite DS-series Substrobes. Microcontroller-based
interface module is powered from the DS-Substrobe via 5-core
(blue-band) sync cable 4103.51 (single strobe) or 4103.52 (dual
strobe). Reverts to manual trigger in absence of power. |
 |
Additional Lighting for Ikelite Housing
|
Triggering via
5-core Ikelite sync. cable gives maximum system functionality.
Slave triggering
is also possible, but precludes use of flash in supermacro mode.
 Strobe
with built-in light, or auxiliary torch to act as focusing light
is recommended. Camera AF system does not work in low light conditions.
Shown left: Ikelite housing with DS-125 TTL Substrobe, 5-core
sync cable 4103.51, and SA-100R ball-joint arm (Substrobe package
#3944.75).
Fittings for the Quick-Grip socket on the top of the handle are
made by Ikelite, Ultralight, and GreenForce. |
Ikelite 6130.80 Housing and Olympus
C-8080 Camera
Test Pictures
Standard Port (54°):
Zoom setting: Full wide. Aperture: f/2.8. ISO: 50.
Light source: Mixed daylight and Ikelite DS-125 with diffuser.
(The white measuring stick attached to the bottom of the test
card is 1m long). |
Standard port. Image geometry,
and corner detail vs aperture:
Standard Port, Full Wide, ISO 50, Ikelite DS-125 flash with diffuser,
aperture as indicated. Corner detail image is full size (same
resolution as original). |
Radial Correction (removal of pincushion distortion and
chromatic aberration):
Same photograph as immediately above, corrected using Panorama
Tools (see the software
optical correction article for an explanation of the method). |
|
PanoTools
Radial Correction
Coefficients
(for flat port,
full-wide zoom) |
|
Discussion:
The use of a flat air-water boundary always introduces some pincushion
distortion and chromatic aberration (colour fringing in off-centre
detail), and these effects worsen as the angle of coverage of
the camera lens increases. The uncorrected photographs above
demonstrate these effects in the worst case, i.e. with the lens
at its most wide-angle setting, which corresponds to a coverage
in air of 75° (35mm equivalent focal length = 28mm). The
pincushion distortion is less than expected, being partially
offset by barrel distortion of the lens, and is not sufficient
to require correction except when photographing subjects with
obvious straight lines and right-angles. Chromatic aberration
will however be noticeable in large prints and displays with
significant edge detail if the full-wide zoom setting is used.
Fortunately, the RGB separation in the camera is accomplished
with very well-behaved filters, resulting in a perfectly apochromatic
system if the user is prepared to take the trouble to apply software radial correction
to the pictures produced. If radial correction is applied, the
camera will give exhibition quality prints of up to about 22.7
x 17" (i.e., 3264 x 2448 pixels at 144 pixels/inch). Note
incidentally, that the radial correction for the Ikelite standard
port is exactly the same as for the camera in the Olympus PT-023
housing with standard port. |
Dome
Port for Ikelite
C-8080 housing.
 Optical
data: Port material: Acrylic, nD=1.492.
Inside radius: 3", 76.2mm. Nominal thickness:
0.218", 5.537mm. |
Optical Data*
Lens System
(zoom setting = full wide) |
35mm equiv.
focal length |
Coverage
in air |
Coverage
UW |
|
Standard lens. Flat port. |
28mm |
75° |
54° |
|
Std. lens, Dome port |
76° |
|
With WCON-08D, dome port |
22.4mm |
88° |
88° |
* Angle of coverage
figures are nominal, i.e., on picture diagonal when lens is focused
at infinity.
With dome port, some coverage is lost in practice underwater
due to lens extension, but optical distortion due to the port
is eliminated in wide-angle photography.
Flat port is recommended for macro-photography, due to strong
de-magnifying effect of dome port underwater. |
|
Dome Port: Test Pictures
Dome Port and WCON-08D (88°
wide-angle):
Full Wide, ISO 50, Ikelite DS-125 flash with diffuser, aperture
as indicated. |
|
Softness of corner detail at f/2.8 is due to curvature of field.
This effect will be less apparent at greater lens to subject
distances. |
Radial Correction (removal of barrel distortion and chromatic
aberration):
Same photograph as immediately above, corrected using Panorama
Tools. |
|
PanoTools
Radial Correction
Coefficients
(for DP with WCON-08D,
full-wide zoom). |
 |
Dome Port without converter lens
(76° wide-angle):
Full Wide, ISO 50, Ikelite DS-125 flash with diffuser, aperture
as indicated. |
The Ikelite dome port for the 6130.80 C-8080 housing is intended
primarily for use with the WCON-08D wide-converter lens, but
can be used without it. In this case, slight corner vignetting
may occur at the full wide zoom setting. Vignetting may be eliminated
by zooming in slightly, or by cropping the final image; or, for
preference, by applying radial correction for barrel distortion.
Radial Correction:
Same photograph as immediately above, corrected using Panorama
Tools. |
|
PanoTools
Radial Correction
Coefficients
(for dome port,
full-wide zoom). |
 |
Comparison
of Ikelite and Olympus C-8080 housings.
|
|
Ikelite 6130.80 |
Olympus PT-023 |
|
Depth rating |
60m |
40m |
|
Use in rough conditions |
Yes |
No
(port mountings too delicate) |
|
Includes tray |
Yes |
No
(but too bulky for use without) |
|
Use internal flash |
No |
Yes (standard port only) |
|
TTL flash converter |
Supplied as standard |
Optional, HeinrichsWeikamp |
|
Supermacro mode with flash |
using Ikelite DS-series SubStrobe |
FL-20 + PFL-01*
FL-36 + PFL-E01
HeinrichsWeikamp converter |
|
Slave triggering** |
Not recommended |
Yes |
|
Accessory shoe. |
No |
Yes |
* TTL flash is possible with the
Olympus FL-20 flash and PFL-01 housing, but this flash system
is too low-powered for wide-angle UW photography and has no focusing
light.
** Slave triggering requires the
internal flash to be swiched on; in which case supermacro mode
will be unavailable. Since neither of the housings can be fitted
with an external macro lens (and there is no room for an internal
macro lens either), supermacro mode with flash is essential if
the user is to realise the full capabilities of the C-8080 camera. |
|
UW coverage (full wide) |
Ikelite 6130.80 |
Olympus PT-023 |
|
Standard port: |
54° |
54° |
|
PPO-05 + WCON-08D |
- |
62.5° * |
|
Dome port: |
76° |
- |
|
Dome port + WCON-08D |
88° |
- |
|
Needs CLA-8 to mount WCON |
No** |
Yes |
* The PPO-05 Flat port with WCON-08D
converter gives pronounced chromatic aberration and pincushion
distortion underwater. Consequently it unsuitable for large prints
and displays unless software radial correction is used.
When the WCON-08D wide converter is used with the PT-023 and
the PPO-05 port; the port must be opened and the CLA-8 unscrewed
before the camera can be removed from the housing. Changing batteries
and memory cards aboard an open boat may be difficult.
** The WCON-08D is held inside the
Ikelite dome port assembly and the CLA-8 adapter tube is not
required. Hence the camera can be removed from the housing without
disturbing the port setup. |
D. W. Knight © Cameras Underwater 2004. |
TTL
Filter
thread M138 x 1.5
Standard port
fits Ikelite 4.2" push-fit UWCC filter #6441.43 B/G.
Pop-up flash cannot
be used..
