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What are Satellite/Sensor Characteristics

Satellite/Sensor Properties for Image ProcessingThis article will bring information and characteristics of satellite/sensor.It is very important to know the characteristics of satellite image, this help user to select and acquire satellite image as per need of research and project. Image can be select based on mapping purpose and for this basic properties are very important for selection of satellite image, which are below-Spectral ResolutionSpatial ResolutionTemporal ResolutionThese properties play significant role for better image classification as per requirement of project. These properties will help to select appropriate image as per need of project for example in first case, spatial resolution may be important if detail information required but in other case if repeatedly satellite images required then temporal resolution become important.Instead of these resolution swath of satellite image is also important as it describe the coverage of satellite image.Below some significant s…

Cartosat DEM Processing using QGIS- Reproject, Clip and Stream Generation

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This article in continuation of earlier article on downloading and processing of Cartosat DEM.https://www.gisoutlook.com/2020/08/download-cartosat-dem-through-bhuvan.htmlIn this article, processing of DEM is explained such as re-project, clip and fill the Gaps and remove error present in DEM. These correction can be performed using GIS functions. Reprojection is needed for correcting geometric errors present in DEM as well as convert projection system one to another. GIS tools can be used for Clipping of DEM is very important especially for watershed delineation, for this clipping boundary based on study will be used. Error present in DEM is defined as sudden extreme high and low values occur in comparison to surrounding values.  Step 1 – Re-project the mosaic DEM using QGISHere we will change the CRS from Geographic to UTM. For this click on Rasterthen Projections followed by Warp (Reproject).
Warp (Reproject) window will popup. Here define Input layer and Target CRS (Co-ordinate Refe…

Download Cartosat DEM Through BHUVAN Portal

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Cartosat DEM Download and Mosaicing Process using QGISThis article is prepared to discuss steps to download Cartosat DEM through bhuvan portal. As this DEM downloaded in tiles so one may need more than one DEM tile for study area. Therefore it is necessary to mosaic these tiles to make a single tile of DEM. In this steps of both processes- download and mosaic are shared to create DEM, which can be further used further for different remote sensing and GIS based applications. Such as Agricultural StudiesWetland studiesWatershed StudiesRunoff and Sediment Discharge StudiesUrban Sprawl MappingTransport Studiesetc.Step 1 - Download freely available DEM data using NRSC-Bhuvan websiteOpen weblink: http://bhuvan.nrsc.gov.in/bhuvan_links.phpFrom this page go to top menu option – Open Data ArchiveA new window will open after clicking on Open data Archive.You need to make user id on this page, so click to Login (on the extreme top right corner) After login Select the area of which you …