What are the sensor/product specifications?
LandSat -8 Data product details : L1T
The level-1 terrain-corrected product (L1T) available to users is a radiometrically and geometrically corrected image. Inputs from both the sensors and the spacecraft are used, as well as ground control points (GCPs) and digital elevation models. The end result is a geometrically rectified product free from distortions related to the sensor (e.g. view angle effects), satellite (e.g. attitude deviations from nominal), and Earth (e.g. rotation, curvature, relief). The image is also radiometrically corrected to remove relative detector differences, dark current bias, and some artifacts. The level one image is presented in units of Digital Numbers (DNs) which can be easily rescaled to spectral radiance or top of atmosphere (TOA) reflectance . Surface reflectance products are also generated from L1T products.
Level 1 Product
A complete level 1 product consists of 13 files :
The 11 band images(OLI bands are bands 1-9. The TIRS bands are designated as bands 10 and 11)
Product specific metadata file (The metadata (MTL) file contains identifying parameters for the scene along with the spatial extent of the scene and the processing parameters used to generate the level 1 product. It is a human-readable text file in Object Definition Language (ODL) format.)
Quality Assessment (QA) image(The QA image is a 16-bit mask, which marks clouds, fill data, and some land cover types.)
The Landsat 8 Cloud Cover Assessment (CCA) system uses multiple algorithms to detect clouds in scene data. Each CCA algorithm creates its own pixel mask that labels clouds, cirrus, and other classification types. The separate pixel masks are then merged together into the final level 1 quality band.
The image files are all 16-bit GeoTIFF images.
More : https://www.usgs.gov/land-resources/nli/landsat/
Sentinal 1A/1B : Interferometric Wide swath mode (IW)
|
SAT |
SWATH |
BANDS |
RESOLUTION |
COVERAGE |
FREQ |
REFERENCING SCHEME |
|
SEN1 Level 1, GRD |
IW mode-250km |
VV+VH
|
5*20m spatial
|
Systematic |
12 day only 1a or 1b , 6days combined |
Spatial reference system : Fiji 1986 Grid(EPSG 3460)) |
Level 1 products are focused using algorithms and calibration data. They can be SLC or GRD products which are georeferenced using a DEM, but are not orthorectified
|
Characteristic |
Value |
|
Swath width |
250 km |
|
Incidence angle range |
29.1° - 46.0° |
|
Sub-swaths |
3 |
|
Azimuth steering angle |
± 0.6° |
|
Polarisation options |
Dual HH+HV, VV+VH |
|
Maximum Noise Equivalent Sigma Zero (NESZ) |
-22 dB |
Sentinal 2A/2B – Level-1C - Orthorectified Top Of Atmosphere
|
SAT |
SWATH |
BANDS |
RESOLUTION |
COVERAGE |
FREQ |
REFERENCING SCHEME |
|
SEN 2
|
290km |
13 |
10,20,60 m band wise |
Systematic coverage
|
10 day sen2a or 2b, 5 days combined |
100km* 100km tiles Military Grid Reference system(MGRS) 29,782 tiles were identified |
SENTINEL-2 is a wide-swath, high-resolution, multi-spectral imaging mission, supporting Copernicus Land Monitoring studies, including the monitoring of vegetation, soil and water cover, as well as observation of inland waterways and coastal areas.
SENTINEL-2 Multispectral Instrument (MSI) samples 13 spectral bands: four bands at 10 metres, six bands at 20 metres and three bands at 60 metres spatial resolution.
Level-1C processing includes radiometric and geometric corrections including ortho-rectification and spatial registration on a global reference system with sub-pixel accuracy.
More : https://sentinel.esa.int/web/sentinel/user-guides/sentinel-2-msi
By When is Data made available :
Generally Data is made available within 24 hours . The sentinel series is available as per the availability on the ESA site .
How is this data product different from NOEDA of Bhuvan?
The Data at Bhoonidhi are Scene based with standard processing and can be used for science analysis in Radiance domain , projects , studies and trends where as at NOEDA-Bhuvan data is available as Tiles.
Temporal Data can be downloaded of almost all acquisitions in the Date range but may require additional processing to improve accuracies.
Data from NOEDA-Bhuvan is more for Theme based Monitoring is updated periodically once or twice a Year.
However both data can be used based on the Accuracy ,Utilization and Application of the User.
POLICY
Which products are priced and how to get?
Data is made available and priced as per ISRO Remote Sensing Data pricing policy .
Can Data be subscribed?
No, User can download data of their AOI daily. However API based downloads will be provided in next versions.
PRODUCT USAGE
Which Open source image processing software tools can be used?
GDAL Library, QuantumGIS for analytics features for both raster and vector, available for both windows and linux. (ArcGIS, ERDAS are proprietary software with such capabilities).
Is it possible to get training for working with these images?
Yes , The Training and outreach services are available : https://www.nrsc.gov.in/ Training Division of Remote Sensing Applications Area is engaged in Capacity Building of user community from various Government/Private/NGOs/Academic Organizations and Institutions in the Area of Geospatial Technology and its Applications, Remote Sensing Ground systems and Navigation systems. Every year we conduct Regular, Special and customized courses to impart training to people working in the domain of Geospatial Applications. Further Bhuvan overview training programmes are also organized for users to increase awareness towards effective utilization of Bhuvan Portal Services. Email id for Correspondence: training[at]nrsc[dot]gov[dot]in
Are there any case studies?
Yes
,
https://www.nrsc.gov.in/Respond_Overview
Student Projects and work: mailto: gmoutreach[at]nrsc[dot]gov[dot]in
How to get free access to earth observation data from NRSC?
The link to Bhoonidhi web application is available at https://www.nrsc.gov.in. The landing page has a link to free access providing web application - Bhoonidhi.
Does this URL work on Mobile devices?
Yes the application works on mobile also.
Is user registration compulsory?
For browsing through the products catalogue user login is not required. But if the user wishes to download the products, registration is compulsory. Due to any reason if after registration you are not able to login, please wait for 15 minutes and retry.
What is a CART?
A Cart is a temporary storage unit to store products of interest for eventual download. User can add/delete selected products to the Cart. Date wise viewing of Cart items is also provided. User has to confirm the items in the Cart. On doing so, the download button is enabled. Selected products can be then directly downloaded from the Cart. In case of delayed download, user will be intimated once the product is available for online download.
I have some suggestions with regards to your service. Where should I post it?
You can fill the feedback form provided at our website. You can also write to us at bhoonidhi[at]nrsc[dot]gov[dot]in
What are the browser configurations to be checked if I face application rendering issues?
If the application is not rendering properly in Internet explorer, it's because there is a setting in IE to 'Display Intranet sites in Compatibility View'. This has to be unchecked in the Internet explorer.
Follow these steps to disable the Compatibility
View / Mode setting in IE 10 and IE 11
Step 1:
Open up Internet Explorer (IE 10).
Click on the Tools menu tab.
Select the Compatibility View settings option.
For IE 11 users:
Open up Internet Explorer (IE 11).
Press the Alt key on your keyboard, this will make a menu bar appear.
Click on the Tools menu tab
Select the Compatibility View settings option.
Step 2:
If you are using IE 10, you will get the following "Compatibility View Setting" page
Uncheck the "Display all websites in Compatibility View" option.
Uncheck the "Display intranet sites in Compatibility View" option.
Do not add GMS or Analyzer URL to the Compatibility View box
If you are using IE 11, you will get the following "Compatibility View Setting" page
In IE 11, the "Display all websites in Compatibility View" option is not available.
Uncheck the "Display intranet sites in Compatibility View" option.
Do not add GMS or Analyzer URL to the Compatibility View box