| Ship's Diary |
| During her time at sea, HMS Endurance will be sending back regular diaries to keep us all up to date with what is happening on this deployment. Use the links below to read extracts from the diary. |
| Vertical Photography by Lt Scott ‘Stimpy’ Simpson RN |
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Vertical Photography is one of the Helicopter’s secondary roles, unique within Lynx operations to 212 Flt and HMS ENDURANCE. We have two cameras on HMS ENDURANCE. These are attached to the side of the aircraft with the lens facing downwards, hence Vertical Photography or VP as we call it.
It is used to assist the United Kingdom Hydrographic Office (UKHO), based in Taunton, with accurately charting this wonderful continent. The film is also used by scientists at the British Antarctic Survey (BAS) to assess both wildlife concentrations and also more importantly accurate positions of the various ice shelves. By comparing the images to older ones they can assess if the ice has retreated due to global warming. SO HOW DO YOU FLY THE CAMERA?  The
aircraft undergoes a specialist role change which takes CPO Rowland and his
team around 3 hours to fit. This includes fitting the camera to the side of the
aircraft, attaching it to the Helicopters power supply and lastly fitting a
periscope through the cabin floor.SO HOW DO YOU KNOW WHERE TO FLY? Both the UKHO and BAS supply the Ship with the start and end of the lines they wish to have photographed, usually with Latitude and Longitude positions. By programming this into the Helicopters Global Positioning System (GPS) the Aircrew can navigate to the start of the lines. BUT HOW DO YOU KNOW WHAT THE CAMERA IS LOOKING AT? The periscope which was mentioned earlier allows the Observer, either Lt Scott ‘Stimpy’ Simpson RN or Lt Simon ‘Clyde’ Collins RN to see exactly what the camera does. The pictures below were taken through the periscope over James Ross Island in the Erebus and Terror Gulf.
SO HOW HIGH DO YOU NEED TO FLY? By flying the Helicopter at high altitudes, normally 8000 feet above sea level the photos appear at a scale of 1:28000. Therefore any distance measured on the photograph can be adjusted for scale to find the real size; i.e. 1cm on the photo is equal to 28000cm. One problem of doing this in colder climates like the Antarctic is the temperature drop. Temperature drops at approx 2°C per 1000 feet, so at 8000 feet with a surface temperature of 0°C, you experience an approximate temperature of -16°C.
 It
is very cold, but by adopting the layer principal the Aircrew keep reasonably
warm. On average we wear anything between 5 to 9 separate layers of clothing.
Stimpy will normally wear 3 pairs of gloves. The first pair made of silk, then
a thin leather pair to trap the heat and then finally a large set of leather
‘Gauntlets’ just to make sure.
And of course a flask of hot coffee and some chocolate always helps. ‘-19°C ! The coldest so far’ SO HOW DOES THE CAMERA WORK? The camera itself works like any normal wet film camera. The clever part is how it compensates for the movement of the helicopter. This is achieved in two ways. When ‘Stimpy’ looks through the periscope he controls the speed of some moving lines in his view finder. By stopping the line on a feature on the ground the camera moves the film at the same speed with which the Helicopter is moving over the ground. This means when the film is exposed it remains over the same bit of ground and therefore you do not get a blurred image. 
The second is altering for the wind. When a Helicopter is affected by the wind, i.e. blown off of course, known as drift, the Pilot has to alter his heading into wind. By telling the Observer how much he has altered the Helicopter the camera can also be offset. The result is that the camera and the Helicopter continue along the intended line. SO HOW MANY PHOTOS CAN THE CAMERA TAKE?  The
cameras still use wet film and are not digital, yet. Digital VP cameras are
still very expensive.
The film itself comes in a roll which is 24cm wide and 76m long. A film will normally allow 270 exposures (frames) and a normal line or run, as we call it, is anything between 8 – 50 frames long. WHAT DO THE PHOTOS LOOK LIKE ONCE DEVELOPED? Below we have some examples of the end product. The pictures are of excellent quality and allow both UKHO and BAS to gain the information they require.
Click here – to see a film montage of Lt Scott `Stimpy’ Simpson using vertical photography |
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