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GEOSCAN MK1 Scanner Specification

Resolution                                 5 Milli radians. 15 Meters at 10,000ft to 4.5 Meters at 3,000ft

Pixels                                        512 re-sampled to 768 to correct for panoramic distortion.

Image Corrections                     Atmospheric back scatter.

Telescope                                  Front surfaced mirrors, SWIR/Thermal  4 gold mirrors. Visible 3 Silver mirrors.

Spectral Filtering                        Diachronic filters

Cooling system                          High pressure, high purity Nitrogen Gas. G size 20 cubic meter gas bottle.

Visible Spectrometer                  5 Channels 0.45 to 0.9 micron, Blue/Green/Red 2 x False Color Infrared

    Detector                                5 by photovoltaic Silicon diodes.

SWIR Spectrometer                  4 Channel 2.0 to 2.5 micron.

    Detector                                4 by Indium Antimonite detector. 

    Cooling                                 4 Joule Thompson cryostat.

Thermal Spectrometer                4 channel 10 to 12 micros.

    Detector                                4 by photoconductive Mercury Cadmium Telluride detector.

Stabilization                               3 Axis inertial stabilization system

    Roll                                       Electronic Start scan offset, 3 milli radian. Vertical gyro reference.

    Pitch                                     Mechanical servo control loop. Vertical gyro reference.

    Yaw                                      Mechanical servo control loop. Rate gyro with electronic integrator.

                                                 Manual Drift offset.

Scan Speed                               Manual True air speed / Height controlled.

                                                 Brush type ring motor.

Computer                                  16 bit 68010 VME computer.

                                                 1 by custom 68010 computers.

                                                 1 by custom RAM/ROM

                                                 1 by custom dual serial port controller.

                                                 2 by custom SCSI hard disk controllers.

                                                 1 by stabilization control system.

                                                 3 by custom 8 channel data acquisition controllers.

                                                 1 by custom video controller.

                                                 1 by custom tape drive controller.

                                                 1 by 2 by 16 character ASCII display.

Data Acquisition                        13 Channel, 8 bit sample and hold ADC.

                                                 Analog Gain and offset.

    Diagnostics                            Analog Oscilloscope.

    Data Storage                          120M Byte 14" Hard disk drive.

    Data Backup                          10" Magnetic tape.

Image Display                            3, 6 and 12 channel Real time scrolling display.

    Resolution                             512 pixels by 512 lines interlaced.

    Color                                     24 bit + 8 bit lookup table mask.

    Lookup table                          8 Hardware lookup table

    Controls                                Hardware pan scroll and zoom. Track ball interface.

Software                                   Written in 68000 Assembler and C.

Authors Contribution 

Electronics                                Data Acquisition system 

                                                 Computer hardware.

                                                 Inertial stabilization system servo controller.

                                                 Video controller hardware.

                                                 Aircraft interface.

                                                 Low noise front end.

Software                                   Micro kernel, Data Acquisition, Data correction, 

                                                 Data storage and archiving, Aircraft interface. 

                                                 User command line interface. Image processing Software

Miscellaneous                            Fix optical, electrical and mechanical design flaws. 

                                                 Scanner Operator for two Years.

Photo Gallery 

Beechcraft Queen Air, 10 Seat passenger aircraft fitted with a aerial survey camera hole. Built in 1959 using WWII technology. We called the Queen Air the flying crowbar. When you wanted to land you pull the engine power controls back one notch and you fell out of the sky.

Queen Air cockpit with a drift sight (MK2 Scanner crew, Pilot, Navigator, Scanner operator).

GEOSCAN MK1 Stabilization platform fitted to Queen Air camera hole.

GEOSCAN MK1 aperture. Bottom view of aircraft. Industrial lunch wrap was the the most optically transparent film suitable to protect the telescope front surfaced gold mirror.

GEOSCAN MK1 telescope and visible, SWIR and thermal spectrometers. Machined out a solid block of aluminium. The equivalent of turning down a tree log down to a toothpick. 


GEOSCAN MK1 Scanner fitted to the Queen Air seat rails (NOAA AVHRR Computer 120M Hard disk, tape drive and cryogenic cooling system..

GEOSCAN MK1 Visible Image of Perth WA, 8 meter resolution.

GEOSCAN MK1 False color infrared Image of Perth WA, 8 meter resolution.

GEOSCAN MK1 Thermal Image of Perth WA, 8 meter resolution.

GEOSCAN MK1 Visible Image of Leonora WA, 15 meter resolution.

GEOSCAN MK1 Thermal Image of Leonora WA, 15 meter resolution.

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