sentences:  However, "WorldView-1" freed capacity on DigitalGlobe's "QuickBird" satellite to meet the growing commercial demand for multi-spectral geospatial imagery.Ball Aerospace built the "WorldView-1" satellite bus and camera using an off-axis camera design identical to "Quickbird", with the instrument's focal plane being supplied by ITT Exelis.The camera is a panchromatic imaging system featuring half-meter resolution imagery.