Degaussing Station - Darkroom light : 無料・フリー素材/写真
Degaussing Station - Darkroom light / intrepidexplorer82
| ライセンス | クリエイティブ・コモンズ 表示 2.1 |
|---|---|
| 説明 | The magnetic influence sea mine was developed and used to great effect by the Germans between 1939-1945. Detecting changes in the earth's magnetic field as allied shipping passed nearby, mines could detonate accurately with devastating results. Lying below the waves, they were almost undetectable. The Allies developed an ingenious counter to this new threat; a series of copper electromagnetic coils could be built into the steel hulls of shipping to alter, and effectively reduce or negate the magnetic signature of the ship using electric current. This method was called coiling. A second, and less effective but cheaper, method was called wiping which involved ships being subjected to an external but temporary electromagnetic field to induce and alter the hull's magnetic field. The unit of measurement for magnetic field is the Gauss, and the name adopted for the process to alter magnetic field was degaussing.However, to do this efficiently, there needed to be a system to measure the magnetic signature of vessels and actively work to tune the signature. And this is the purpose of this facility at Piers Cellars.Known locally as the camera room, this facility at MOD Piers Cellars is a scientific time capsule with roots back to the Second World War. The first reference I may have found is from 1945 when there was an Admiralty proposal to "take over A/S Fixed Defence Station at Pier Cellars, Cawsand Bay as sea experimental station for Admiralty Research Laboratory" (ADM 1/22326).Where were the cameras?Operated by QinetiQ as one of 15 MOD-owned facilities across the UK through the Long Term Partnering Agreement (LTPA), Piers Cellars is a historic and still relevant site for the gathering of magnetic data. The site is described on the T3E website as providing "electromagnetic ranging of ships and submarines. An electromagnetic 20m open sea range is located at Pier Cellars. In addition, there is an electromagnetic 9m open sea range at Weymouth. These ranges automatically gather magnetic signatures of vessels entering and leaving Plymouth and Portsmouth Harbours.The site is still MOD owned and operated by QinetiQ, although the camera room has lain empty for over 30 years. |
| 撮影日 | 2023-05-23 11:34:34 |
| 撮影者 | intrepidexplorer82 , United Kingdom |
| タグ | |
| 撮影地 | |
| カメラ | ILCE-6600 , SONY |
| 露出 | 0.033 sec (1/30) |
| 開放F値 | f/6.3 |
| 焦点距離 | 17 mm |