A low cost portable remote sensing system has been established for use in crop health assessment and large scale land resource assessment. The important features of the system are; it monitors the near infrared, which is important for agricultural applications, and it incorporates position and attitude measuring equipment allowing for geo-rectified images to be produced without the use of ground control points. The equipment is designed to be hand held and hence requires no structural modification to the aircraft. Usually, the portable remote sensing consists of an inertia measurement unit (IMU) which accelerometer based, low-cost GPS devices and a small format false colour composite digital camera which is cheap, easy to install and suitable to be carried on the small aircraft such as Cessna 152. This book, therefore, provides a new method to deal with the low cost portable remote sensing devices and it should be able to help individual or small company in managing the agriculture field.