Use is made of the built in video capability of many of the modern digital cameras for framing and focusing the image before stills capture. The camera can be set in automatic mode thereby utilising in built intelligent electronics, ensuring that most images are correctly exposed and focused. When captured, a review of the image is displayed in video format for a period of two to ten seconds dependant on preset times, allowing for quality assurance prior to moving to the next inspection site.
The operator can remotely control the camera by using a GUI (Graphic User Interface) which can give access to all controls normally available in modern digital cameras along with the opportunity to set long line video drive compensation, choose to display video on the GUI window or switch off the flash if sufficient ambient light is available. The output from a humidity sensor in the camera can also be displayed.
In addition to control of zoom and image capture, manual control of focus, aperture and shutter speed can be easily selected. Full control of the camera through the menu icon can be gained allowing a myriad of options such as date and time setting, video standard changes and white balance select.
Intervalometer Function
Some of the more advanced cameras have a built in Intervalometer function which allows the camera to be deployed autonomously and pre-programmed to capture images at set intervals. This function has been successfully used by Ocean Research Institutes and produced quite phenomenal results far beyond their expectations. A 6000 metre depth rated camera was deployed and locally powered on a Lander which is sent to the Ocean floor for hours, days or even months in order to gather scientific data before being sent a command to return to the surface.
Cameras can also be simply triggered by a bottom contact or pressure switch allowing an image to be captured as the camera approaches the bottom or at a preset depth.
GUI Camera Control OE14-208 Camera
Replay Thumbnails
Surface Control
On surface controlled systems the images already stored in the flash memory (which can be upgraded to 4GB) can be replayed in the form of thumbnails or full image. The option to delete any images can be chosen at this time.
Control of the surface linked camera is normally by RS232 or RS485 serial link with the images being uploaded from the camera over a short USB link when it is returned to the surface. USB to fibre optic converter board sets are available which allows the camera to be controlled and images uploaded over up to ten kilometres of fibre optic cable.
Diver underwater digital camera housings have been available for some time now, although to date these have had limited depth ratings and have been aimed at the professional SCUBA photographer and sports divers and have provided considerable control of camera settings. A more rugged unit suitable for the commercial diver has now been developed. It is rated to 250 metres and its operation kept as simple as possible as it is recognised that not all divers are professional photographers and only direct control of zoom and shutter release is provided. In addition to automatic mode two selectable preset options can be programmed for selection of focus and exposure as appropriate. One of these options can be programmed to allow digital video clips to be taken.
Once the images have been uploaded to a PC they can be emailed to shore. Therefore, from an image being taken underwater it can now be on the PC of a decision maker thousands of miles away within a few minutes. Compare this with a photograph of yesteryear having to be developed and posted or hand carried to the desk of the same decision maker. In addition that decision maker now has the capability of zooming in to fine detail and spotting defects that the human eye may not see even if present at the work site.
Advantages of filing and retrieving digital images and the physical space savings are obvious. There could even be an argument made for reducing the amount of video footage required in certain circumstances.
An initiative run by Southampton Oceanography Centre called The Serpent Project has successfully brought together Oil Companies, Operators and Equipment Suppliers to take advantage of what would otherwise be standby ROV time on board drilling rigs. Marine Scientists can carry out or direct research in the oceans around the rig utilising these ROVs and as part of this research use digital cameras, which have produced some startling digital images. Examples are attached but be sure to visit http://www.soc.soton.ac.uk/GDD/serpent/ for further information and images.
Prawn and Hole Sponge
My Little Sea Pony
ROV pilots enthusiastically involve themselves in the project and sometimes try to baffle the Marine Scientist!
Digital Underwater Cameras
