Dr. K. M. M. Rao
Rajendra Kumar. S
National Remote Sensing Agency, Dept. of Space, Balanagar,Hyderabad, 500 037
Mailing Address : S. Rajendra Kumar, HSPDS, DPA, NRSA, Balanagar,Hyderabad, 500037
Phone No. 040-3884417, Fax: 040-3879307, Email – [email protected]
The applications of remote sensing data have acquired new dimensions with the successful launch of many high-resolution satellites. High-resolution satellites are now providing imagery that yields much finer details of the earth’s surface. These satellites essentially produce images that approach air photo quality in terms of discernable detail. The data is extensively used for large-scale mapping, town planning and strategic applications.
The imaging of high-resolution data should ensure the effective transformation of the finest details contained in a digital image on to the photographic media for better visual interpretation. For cartography , high resolution data in Panchromatic and multispectral imaging mode may be suited to generate map products in 1:5000 and 1:10,000 scale. Due to the large data size of the high-resolution data, large scale photoproducts cannot be generated using conventional film recorders due to Spot size & writing size limitations.
This prompted the need for Large Format Photowrite (LFPW) to image high-resolution data for large-scale mapping and other applications. LFPW has been derived from Small Format Film Recorder technology developed by National Remote Sensing Agency (NRSA) to over come the limitations of conventional recorders. LFPW is an electro-optic-mechanical system built with high degree of precision for optimum reproduction of digital images at varying scales on Photographic paper. It generates B/W & Color images up to 1mtr. X 1mtr. size from a digital file by exposing directly on a Photographic media. By eliminating the intermediate film, film processing, enlargement stages, this new technology promises lot of advantages over conventional recorders, which includes improved image quality, low turn around time and reduction in cost per product.
Presently Satellites like IKONOS & Quickbird provide high-resolution data wherein Photoproducts for these are generated on LFPW at a larger scale to derive maximum advantage. A continuous development of sensor technologies is guaranteed for the next decades by many national and international remote sensing missions. Hence there is more emphasis for exploring new technologies to accomplish Imaging of high-resolution data for strategic applications.
A detailed study of High Resolution Data Imaging on Large Format Photowrite is described in this paper.