1 What Information Do We Need, for Which Astronomical Problem? -- Astrometry -- Photometry -- The Photometry of Extended Objects: Diode Array Detectors and Interactive Data Processing -- Trends in Astronomical Spectroscopy -- 2 Acquisition and Storage -- Information Retrieval by Microdensitome Try -- Fourier Techniques -- Television Detector Techniques -- On Line Digital Correlation of Photon Counting TV Images for Stellar Interferometry -- Photon-Counting Detector Arrays Based on Microchannel Array Plates -- Performance of the MIT Silicon Vidicon Imaging System at the Telescope -- A Self-Scanned Silicon Diode Array for Astronomical Photometry -- Image Detectors for Recording Astronomical Ultraviolet Spectra -- Mesure Des Contours de Raies par les Techniques de Television -- Photometry using Electronographic Techniques -- Integrating TV System Development at Cambridge -- Sec Vidicon System for a Balloon Ultraviolet Stellar Spectrometer -- Problems of Oversampling with Sec Vidicon Television Systems -- Some Experiments with an Sec Image Tube for High Precision Multi-Colour Photometry of Galactic Clusters -- 3 Processing Hardware -- Four Years Experience in APMS Star Plate Processing - Results and Future Plans -- The Use of the "Galaxy" Machine at the Royal Greenwich Observatory -- The Fully Automatic Program-Controlled Microdensitometer-Comparator of the Astronomical Institute at Utrecht -- The Grant Measuring Engine -- The U.S. Naval Observatory's Automatic Measuring Machines -- The Two-Coordinate Grant Machine in Long-Focus Astrometry -- The Cosmos Facility at the Royal Observatory Edinburgh -- The ESO S-3000 Measuring Machine -- Iris - A Two Axis Comparator and Microdensitometer using Two Different Scanning Modes -- Machine a Mesurer de L'Observatoire de Haute Provence -- The Design of the New S.R.C. Automated Photographic Measuring System -- The Computer Controlled Comparator Astroscan -- A Simultaneous Six-Channel Microphotometer with Computerized Data Acquisition -- A Very Simple Digital Microdensitometer-Comparator -- Photoelectric Spectroscopic Plate Measuring Machine Built at the Meudon Observatory -- 4 Software Techniques -- Software Techniques for Image Processing -- Problems of Machine Independency and Interactive Matters -- Aperture Synthesis -- Interactive Computer Reduction and Display of Radio Super-Synthesis Maps -- The Design of Vamp Software for the Measurement and Reduction of Stellar Spectrograms -- Development of Digital System for Stellar Spectra Reduction at Toru? Observatory -- Evaluation of Master Scans of Photographic Stellar Images -- Image Processing Systems Developed at MIT to Handle Silicon Vidicon Images and Spectra of Astronomical Objects -- Handling of 'Galaxy' Photometry -- 5 Applications to Astronomical Problems -- Some Preliminary Results Obtained with a TV Camera in the Field of the Observation of Visual Double Stars -- Echelle Spectra Image Processing for the International Ultraviolet Explorer -- Semi-Automatic Determination of Equivalent Widths -- Accuracy and Results of Spectrophotometry with Objective Prism Plates -- Le Centre de Depouillement de Cliches Astronomiques -- Intercomparison of Ground Based and Satellite Pictures of the Sun -- Flying-Spot Analysis of Solar Images -- Removal of Vignetting from Apollo Low Light Level Photographs -- Search of Significant Features in a Direct non Parametric Pattern Recognition Method. Application to the Classification of a Multiwire Spark Chamber Pictures -- Lock-In Image Subtraction Detectability of Circumstellar Planets with the Large Space Telescope -- Digital Image Centering, I.