The first permanent earth observation satellite, today known as Landsat 1, was launched 33 years ago. With a ground resolution of 80 metres, the Landsat Multispectral Scanner images provided an...

QuickBird imagery offers the highest spatial resolution so far available from a commercial satellite. Resolutions as low as 60cm, combined with high positioning accuracy, make it well suited for mapping...

Use of the digital camera Vexcel UltraCam D was introduced in early 2004 by Aerodata International Surveys. Up until then solely analogue photo cameras such as the Zeiss LMK 2000...

Receiver position is calculated from the position of satellites and the distances to them. Distance is calculated from the time a radio signal travels between satellite and receiver. But how...

Anomalies such as building-lean result from the processing of traditional orthorectified imagery and this limits its use in urban areas. However, the arrival of digital sensors has meant fully orthorectified...

Jena-Optronik GmbH (Germany) has announces the new Jena Airborne Scanner JAS 150, a second generation digital sensor with enhanced flexibility and reliability. Developed for photogrammetry, mapping and remote sensing of...

The 4th International Symposium on Digital Earth was held in Tokyo, Japan from 28th to 31st March 2005 (see review 'Digital Earth Facing Challenges' July 2005). The head of the...

The 4th International Symposium on Digital Earth was held in Tokyo, Japan from 28th to 31st March 2005 (see review 'Digital Earth Facing Challenges' July 2005). The head of the...

Excessive groundwater extraction is probably the main factor causing land subsidence in urban areas of Indonesia. Decreases in groundwater level may reach 15 metres a year. Monitoring of land subsidence...

Kunming Surveying and Mapping Institute (China) has successfully established the first Leica Geosystems GPS reference station network in Kunming for pushing forward the digital city project in Kunming. This project...