Background

The Isle of May is located in the The Firth of Forth on the East coast of Scotland. It is a breeding colony for the Grey Seals and the home of many species of seabird, which is why the Scottish Seabird Centre in North Berwick were keen to install a live camera link there.

In the spring of 2001 The Scottish Seabird Centre asked Outersight to tender for the design and installation of a remote observation system on the Isle of May.

Location

When we first looked at the chosen location we immediately recognised that there were several challenges, both technical and environmental, to be overcome before we could even set foot on the island.

The location overlooked a small beach that was a popular Grey Seal haul-out during the breeding season, as well as being within a metre of several Shag nesting locations. The location would frequently be in the wave splash zone during a strong Westerly gale, so we knew that the camera would have to be extremely robust and waterproof to survive the conditions that it would experience during the winter. Fortunately the location was a rocky outcrop, which meant that we could anchor the 1.5 metre high stainless steel pole, that the camera attaches to, directly to the bedrock using 0.5 metre stainless steel rods.

Camera

When we came to specify the camera and pan and tilt system, we knew that we had a few tough criteria to meet the key ones being:

• Reliability – the island can be very hard to get to for much of the year, especially during the winter It is also an expensive trip involving a boat charter and long drive to the nearest harbour, so regular maintenance visits were out of the question.
• High video quality – the images are displayed on a 2.5 metre wide projection screens, so the video quality had to be very high in a variety of lighting conditions. Normal CCTV and the Broadcast quality equipment that we tried could not offer the level of intelligent picture optimisation that we required
• Camera stability – in high winds a normal CCTV style box camera wobbles a great deal; when the camera is zoomed in this would render the video image unusable, so we needed a camera setup with an extremely low wind profile
• Low power consumption – there is no mains power supply to the island, and with the large quantity of birds in the vicinity a wind generator was out of the question, so solar power had to be used so the power consumption of the system had to be as low as possible
• Cost - the Scottish Seabird Centre is a charitable organisation, consequently costs had to be kept as low as possible.

After much research and testing we eventually decided that a camera from British manufacturer Forward Vision Systems would meet or exceed all our requirements. After lengthy consultation with FVS we decided on the exact specification for the camera, which includes auto focus and an 18x optical zoom allowing good views of distant objects, and amazing close up views of the seals and birds closer to the camera.

Power

As there was no power available near to the camera, and wind generation was not acceptable with the bird population, we had to decide whether we generate power locally at the camera using solar panels, or run a 500 metre cable back to the Scottish Natural Heritage warden’s quarters where there is a solar generation plant. To minimise the visual impact of the system we decided to install the long cable, and that by adding 4 solar panels to the SNH solar system we would generate more than enough power. The cable was attached to the disused foghorn compressed air pipe for most of the 500 metres. Where there was no compressed air pipe,  the cable was laid on the surface to minimise disturbance to the ground, the only trenching was where the cable crossed a path. We have found from experience that the cables are rendered invisible within a few months by the growth of grass.

Signal Transmission

The distance from the camera location to the SSC is approximately 17km, which meant that a high power microwave link in the 13GHz band would have to be used for the video and audio signal. The low height above sea level of the camera meant that we had to site the transmission equipment further up the cliff to reduce interference from shipping and waves, and to counteract the radio propagation issues presented by the curvature of the earth. Reliability was a key criteria for choosing the link equipment, and we decided that the VML series of microwave transmission equipment from Continental Microwave Ltd was most suited to the job.  The VML series of transmission equipment is a mature design with proven reliability in extreme locations. Outersight made all the arrangements for the relevant operators license from the Radio communication agency.

The control information could not be sent over the microwave link, so a UHF radio data link was specified to enable the camera movement to be controlled remotely. This operates on a deregulated frequency and did not require a license from the Radio Communications Agency.

All the equipment on the island has been painted in a mottled brown paint to allow it to blend in with the surrounding area.

Control and Display

Most of the time the camera is controlled by visitors to the SSC, this means that the control interface has to be easy to use by all ages, sizes and technical abilities, so we opted for a simple dual joystick system, one for left, right, up and down, and one for zoom in and out. When designing the control panel we recognised the fact that some people, particularly young children can be quite rough with the joysticks (by rough we mean literally hanging off them), and this was taken into account in the type of joystick and mounting that was used.  

As the staff at the SSC conduct guided interpretation using the camera, a wireless control panel has been provided so that camera presets and control is available whilst the interpreter talks to the audience.  These remote controls link in to an AMX Axcent 3 master controller, which also controls the associated audio visual equipment in the centre. Outersight programmed the AMX controller and have since added extra functions to assist the interpreters with their work.

When specifying the means of video display we considered the pro and cons of several display devices. Picture quality, image size and running costs were considered the key points, and we decided that an LCD projector mounted from the ceiling would give the best compromise of these points. The live video images are projected onto a 2.5 metre wide screen by a SONY VPL VW10HT, which produces a high quality video image and very little noise. With a 2000 hour lamp life this requires around 2 replacement lamps per year at about £400 per lamp.

The observation system went live in November 2001 on schedule and on budget . The camera system has now been operational for over 4 years, and has proved to be very reliable, despite the harsh environmental conditions that it encounters through out the year.  The Isle of May camera is the most popular interactive exhibit at the Scottish Seabird Centre.

Update

We have recently added a second camera on the Isle of May, allowing even better views of the seals and seabird cliffs throughout the year. Check out the pictures on the Scottish Seabird Centre webcam page.