Underwater
PhotographsOne of the stated aims of the expedition, was 'making an underwater video and stills photographic record of the site', in other words to gather footage that could be used for scientific purposes, so that the morphology, colour and size of the ikaite could be captured underwater, and relayed to others. This aim was particularly important, because, until our expedition there were no underwater photos of the site.
Photographs & film footage were also taken with more specific aims in mind:
The equipment used, had to be fairly specialised in that it need to be waterproof. The underwater still photos were taken using a Nikonos V with a TTL strobe (flash). The Nikonos V is a fairly robust unit as cameras go and will survive a severe flooding in the case of an 'O' ring failure etc, nevertheless, despite taking a spare O ring set, the expedition also took a 'spare' Nikonos V. Both Nikonos cameras came with a relatively wide-angle 28mm lens (equivalent to 35mm underwater). A macro extension for close-up photography was also taken, but not used.
Land photos were taken with a variety of cameras, though principally with a Canon EOS 100 (with auto-focus), and with 28-80mm and 100-300mm zooms, macro extension tubes and a semi-fish eye lens. A Benbo tripod was used for certain shots.
The video footage was taken using a Sony TR707 camcorder with Hi-8 film. For underwater footage the camcorder was placed in an AVS 8.0 'Video System' underwater housing. This housing is a very robust unit, with an anodized, cast aluminium body with a waterproof rating to 100m - the depth limit for SCUBA divers is only 50m. Despite its robustness, the housing was always handled with care, such that, prior to all dives, the dome port was always lowered into the water from the boat to check for leaks. The diver would also check for leaks on the descent - a task made easier because of an in built audio-visual alarm.
The AVS housing leaked once - grit on the O ring - but no damage was entailed either to the film, or to the camera, or for that matter to the O ring - though this would not have been a problem, as, with everything, we had a spare.
We also had a problem with the batteries, which stopped powering the video, though still 'half' charged. To counter this, JB constructed a battery discharger, after which we had no problem.
No lighting was used with the video for daytime (underwater or land) filming. On the one occasion in which we were filming at night (on a dive), more than sufficient lighting was provided with two underwater torches - UK400 Rechargeables (18 Watt Xenon Bulbs).
The provision of lighting for the underwater filming was a matter of concern for us prior to the expedition, however following advice we were told that we would not need it, and indeed this seems to be the case. In fact the sensitivity of the CCD was such that when panning up the ikaite columns into the light, the film tends to be 'over exposed', and indeed some of the best footage comes from a dive when the sky was overcast and the underwater visibility relatively low.
Lighting is more important for photographic film and also if you wish to capture the true colour of underwater objects - the spectrum of natural light is absorbed by the water at different rates, red being absorbed first and such that at depth only blue is left.
As with the precautions taken with the stills camera and film, the first bit of video footage was replayed through the camcorder viewer, to check that exposure settings and focus etc were working correctly. However, following advice that each time a Hi-8 tape is played its quality is degraded - not a problem for holiday footage perhaps, but a problem if you wish to get footage broadcast - no other tapes were reviewed in this manner (or any other). Since the expeditions return, these tapes have been played only twice, once to transfer the images to Professional VHS - these VHS tapes were used as our master tapes for the production of our first edited video - and once to transfer the images to Professional Digital Beta - which we will use for any further broadcast-quality footage.
Considering the importance of the need to make a photographic document of the ikaite columns and the fact that nobody likes coming home to find that their camera wasn't working properly, with regards exposure settings etc., it was deemed advisable to take and develop some Black and White film in the field. A dark room was improvised by waiting till the few hours of darkness arrived and then loading the film from the cassette to the development tank spiral in a sleeping bag. Prints and colour film developing in the field were impractical.
This test of the camera was in fact quite prudent, revealing the problem of flat batteries and batteries not lasting long enough underwater.
Of the 90 films taken, 77 rolls were used. The success rate of the films was about 3-4 photos of a sufficient standard, on each roll. Two films did not work, but the footage was covered sufficiently by the other cameras.
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