Photogrammetric Mapping

Advantages of softcopy photogrammetry

This comparison of analytical and digital techniques has shown that Digital Photogrammetry have greater advantages to analogue / analytical plotters as better stability (geometry and radiometry), good accuracy, and the ability to process images. It is also possible to display vector data in the images on the screen and to produce transformed images (recti?cation, Orthophoto). Today the handling and use of digital images on standard PC’s is possible up to the ?nal production of orthophoto mosaics and contour lines without problems. Digital Photogrammetry Workstation offer other additional products including ?y-through, image drapes, view shed analysis tools, orthophotographs and image analysis tools.

There are several other advantages connected with using digital images which are as follows:

• Production Ef?ciency is very good.
• No Instrument calibration is needed.
• Measurements are automatic and faster.
• No repetitive IO, RO & AO to start a model.
• Stereo images can be reconstructed very fast.
• DTM and Orthophoto generation is automatic.
• Single model as well as strip / block orientation is possible.
• No constraint of focal length bracket as in analogue system.
• Digital images are more stable as compared to ?lm material.
• Integration with Remote Sensing facility, real time data updation.
• 3- D graphical superimposition facility for automatic feature extraction.
• Automatic measurements possible with correlation techniques.
• Digital image processing techniques can be used for image enhancement.
• Simple to Operator, no wear and tear of mechanical and optical parts compared to Analogue and Analytical Instruments.