Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color...
-
date post
18-Dec-2015 -
Category
Documents
-
view
297 -
download
2
Transcript of Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color...
![Page 1: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/1.jpg)
Characteristics of remote sensing systems
![Page 2: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/2.jpg)
Different kinds of images
• Panchromatic image• True-color image• False-color image
![Page 3: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/3.jpg)
Panchromatic image
• If airborne cameras use black/white film or satellite sensors use a single band, it produces panchromatic image (gray scale image)
![Page 4: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/4.jpg)
Color composite
• Color primaries: RGB (Red, Green, Blue)
• Many colors are formed by combining color primaries in various proportions
• Same principles apply to producing color images taken from airborne cameras or satellite sensors
![Page 5: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/5.jpg)
Greyscale vs. RGB
• Greyscale is typically used to display a single band
• RGB (“Red”, “Green”, “Blue”) images can display 3 bands, corresponding to the red, green and blue phosphors on a monitor.
![Page 6: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/6.jpg)
True color and false color images
• True color image- the color of the image is the same as the color of the object imaged.
• A false color image is one in which the R,G, and B values do not correspond to the true colors of red, green and blue. The most commonly seen false-color images display the very-near infrared as red, red as green, and green as blue.
• For instance, different types of vegetation might appear as blue, red, green or yellow. Intuitively, vegetation would appear green.
Vegetation appear red in this color composite
![Page 7: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/7.jpg)
Describing Sensors
- Spatial resolution
- Spectral resolution
- Temporal resolution
- Radiometric resolution
![Page 8: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/8.jpg)
Spatial resolution
• Spatial: pixel size; The size of the smallest possible feature that can be detected.
• In a digital image, the resolution is limited by the pixel size, i.e. the smallest resolvable object cannot be smaller than the pixel size.
• Fine or high resolution image refers to one with a small resolution size. Fine details can be seen in a high resolution image.
• Coarse or low resolution image is one with a large resolution size, i.e. only coarse features can be observed in the image.
• Aerial photo has higher resolution • The image resolution and pixel size are not equivalent.
![Page 9: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/9.jpg)
Spatial resolution
A low resolution MODIS scene (1km) A very high resolution image acquired
by the IKONOS satellite (1m)
![Page 10: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/10.jpg)
Spectral Resolution• The number, wavelength position
and width of spectral bands a sensor has
• A band is a region of the EMR to which a set of detectors are sensitive.
• Multi-spectral sensors have a few, wide bands(several spectral bands)
• Hyper-spectral sensors have a lot of narrow bands (hundreds of spectral bands)
![Page 11: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/11.jpg)
Spectral Resolution
Multi-spectral
hyper-spectral
![Page 12: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/12.jpg)
Radiometric resolution
• The radiometric resolution of an imaging system describes its ability to discriminate very slight differences in energy (intensity level)
• It depends on:
1- Radiance range-bits/pixel
2- Signal to noise ratio (S/N) of the detector. The ratio of the level of the signal carrying real information to that carrying spurious information as a result of defects in the system.
![Page 13: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/13.jpg)
Radiometric Resolution
2-bit = 4 radiance levels 8-bit = 256 radiance levels
The finer the radiometric resolution of a sensor, the more sensitive it is to detecting small differences in reflected or emitted energy .
![Page 14: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/14.jpg)
Temporal resolution
• How frequent a given location on the earth surface can be imaged by imaging system.– For satellite image, it can be regular
(satellites are orbiting the earth in regular time interval)
![Page 15: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/15.jpg)
Earth Resource Satellites Operating in the Optical Spectrum• Landsat • SPOT • Meteorological Satellites
– NOAA satellites – GOES satellites
• Ocean Monitoring Satellites – Radar Satellites – Seasat – ERS-1 – JERS-1 – Radarsat
![Page 16: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/16.jpg)
Introduction
• Satellite systems operating within the optical spectrum (0.3-14 m): UV, visible, near-, mid-, and thermal IR wavelengths
• Landsat and SPOT
• Higher resolution, contemporary programs (IKONOS, QuickBird)
![Page 17: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/17.jpg)
Earth history of space imaging
• Cameras on rockets (Germany 1891, 1907)
• 1946-1950: beginning of space RS with small cameras aboard V-2 rockets (NM, USA)
• Meteorological satellites (initial application) TIROS-1 (1960)
• Corona, a military space imaging reconnaissance program (1960 - 1972).
![Page 18: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/18.jpg)
Earth history of space imaging
• Manned space programs:– Mercury, Gemini, Apollo– Alan Shepard (1961): Made a 15-min suborbital
Mercury flight on which 150 excellent photographs were taken
– John Glenn (1962): Made 3 historic orbits around the earth and took 48 color photographs during Mercury mission MA-6
• Gemini GT-4: geological application
• Other geographic & oceanographic phenomena
![Page 19: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/19.jpg)
Earth history of space imaging
• Apollo 9: multispectral orbital photography for earth resource studies
• 1973: Skylab: Earth Resources Experiment Package (EREP)
• 1975: US-USSR Apollo-Soyuz Test Project (ASTP) hand-held cameras, disappointing results
![Page 20: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/20.jpg)
Landsat Satellite Program Overview
• Earth Resources Technology Satellites (ERTS) program (1967): a planned sequence of six satellites
• In 1975, ERTS was renamed by NASA “Landsat”
![Page 21: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/21.jpg)
Landsat Program
• During the experimental Landsat phase, imagery was disseminated by Earth Resources Observation System (EROS) Data Center at Sioux Falls, SD.
• Satellites were operated by NASA and USGS was handling the data distribution.
![Page 22: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/22.jpg)
Landsat Program
• Gradually, NOAA took over and the Landsat program operation was transferred to a commercial firm (Earth Observation Satellite Company – EOSAT).
• Landsat-7 operation reverted to the government; EROS Data Center is the primary receiving station, processing and distributing the data.
![Page 23: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/23.jpg)
Landsat Program
• Landsat-1,-2,-3 images are catalogued according to their location within the Worldwide Reference System (WRS), by specifying:
– a path (each orbit within a cycle)– a row (individual nominal sensor frame
centers)– a date
![Page 24: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/24.jpg)
Landsat Program
![Page 25: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/25.jpg)
Landsat Program
• E.g. the WRS has 251 paths for Landsat –1, -2,-3 (number of orbits to cover the Earth in 18 days).
• Paths are numbered from 001 to 251, E to W, row 60 coincides with the equator.
![Page 26: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/26.jpg)
ERTS-1 (Landsat-1)
• Launched by a rocket on 7/23/1972
• Operated until 1/6/1978
• The first unmanned satellite specifically designed to acquire data about earth resources on a systematic, repetitive, medium resolution, multispectral basis
• 43 US states & 36 countries
![Page 27: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/27.jpg)
Landsat Satellite Program Overview
• Landsats carried combinations of 5 types of sensors:
– Return Beam Vidicon (RBV) camera systems– Multispectral Scanner (MSS) systems– Thematic Mapper (TM)– Enhanced Thematic Mapper (ETM)– Enhanced Thematic Mapper Plus (ETM+)
![Page 28: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/28.jpg)
Landsat 1-3 orbital characteristics
• Sun-synchronous orbits: The satellite crossed the equator at approximately the same local sun time (9:42) every day
• Lunched into circular orbits at 900 km • Near-polar orbits travels northwards on one side
of the earth and then toward the southern pole on the second half of its orbit, 14 times a day
• Passing same point every (coverage repetition) • Sensors aboard imaged only 185 km swath• Globe coverage every 18 days (20 times/year)
![Page 29: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/29.jpg)
Sensors Onboard Landsat-1,-2,-3
• Landsat-1,-2:
– A three-channel Return Beam Vidicon (RBV) camera system
– A four-channel MSS system
![Page 30: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/30.jpg)
Return Beam Vidicon (RBV)
• Nominal ground resolution of cameras: 80 m
• Spectral sensitivity per camera: similar to a single layer of color infrared film (band 1: green (0.475-0.575), band 2: red (0.58-0.68), band 3: near IR (0.69-0.83)
• Failed within weeks of Landsat 1
![Page 31: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/31.jpg)
Landsat-3
• Spectral sensitivity: green to near-IR
• 30 m nominal ground resolution
![Page 32: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/32.jpg)
MSS System
• The MSS onboard Landsat-1,-2,-3 covered a 185 km swath width in 4 wavelength bands (green, red, and 2 near-IR) designated as bands 4,5,6,7.
• Note: In Landsat-4 and -5 they were bands 1,2,3,4.
• On Landsat-3 there was a band 8 (thermal band) but this failed shortly after launch.
![Page 33: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/33.jpg)
Orbit Characteristics of Landsat-4 & -5
• In these missions, orbits were lowered from 900 to 705 km. This was done to aid in the improvement of the ground resolution of the sensors on board.
• 14.5 orbits/day (orbit period: 98.9 min)
• 16-day repeat cycle for each satellite (coverage cycle)• Local crossing at about 9:45 am.
• Landsat-4 &-5 WRS: 233 paths (001-233, E-W), with 001 crossing the equator at 64°36’ W longitude
• Same number of rows (60 coincides with the equator)
![Page 34: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/34.jpg)
Sensors Onboard Landsat-4 & -5
• MSS and TM sensors
• MSS transmits 15 megabits/sec
TM transmits 85 megabits/sec
• MSS data are collected using a 80-m ground resolution cell
• MSS bands 1-4 in Landsat –4 & -5 corresponds to 4-7 of the Landsat–1,-2,-3
![Page 35: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/35.jpg)
Sensors Onboard Landsat-4 & -5
• MSS used a quantization range of 6 bits (64 digital numbers), but TM uses a range of 8 bits (256 numbers) for its onboard analog-to-digital signal conversion.
• Finer radiometric precision Greater sensitivity to changes
![Page 36: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/36.jpg)
Sensors Onboard Landsat-4 & -5
• Thematic Mapper (TM)• TM: highly advanced sensor, improved over MSS• 7 bands, (0.45-12.5 μm)
– TM data are collected using a 30-m ground resolution cell (thermal band: 120 m).
– The size of area viewed on the ground is called the resolution cell
– TM bands are more finely tuned for vegetation discrimination than those of MSS
– TM Data are best for use in several application areas (bathymetry, rock type discrimination, etc.)
![Page 37: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/37.jpg)
Landsat TM Vs. MSS
• TM images cover a wider range of applications than Landsat MSS images, due to more spectral bands and improved spatial resolution.
• MSS images are better for large area analyses (geologic mapping)
![Page 38: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/38.jpg)
Landsat TM Vs. MSS
• More specific mapping (detailed land cover) is difficult on MSS because many pixels are “mixed” pixels
• TM’s decreased Instantaneous Field of view (IFOV) produces less mixed pixels
• IFOV is the angular visibility of the sensor
• Incorporation of mid-IR bands (5 & 7) has increased the vegetation discrimination of TM data
![Page 39: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/39.jpg)
Landsat-6 Planned Mission
• Launch failure on 10/5/93
• Landsat-6 would have occupied an orbit identical to that of Landsat-4 & -5
• The sensor of this mission was the Enhanced Thematic Mapper (ETM) (same bands, same resolution)
![Page 40: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/40.jpg)
Landsat-6 Planned Mission
• ETM’s major improvement over TM was the addition of an eighth “panchromatic” band with a spatial resolution of 15 m.
• Another improvement was the use of a 9-bit analog-to-digital converter.
![Page 41: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/41.jpg)
Landsat-7
• This program is jointly managed by NASA and USGS (http://landsat.gsfc.nasa.gov/announcements/program_update.html)
• Launched on April 15, 1999 (http://landsat.gsfc.nasa.gov/main/project.html)
• A new sensor : Enhanced Thematic Mapper Plus (ETM+)
• Same swath as ETM, similar orbits and characteristics• Swath: The area imaged on the surface.
![Page 42: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/42.jpg)
ETM+
• Resolution– Bands1-5, 7: 30 meters– Band 6 (Thermal band): 60 meters– Band 8 (Panchromatic band): 15 meters
• Complete global view four times a year
![Page 43: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/43.jpg)
ETM+
• Ground transmission of data either directly or stored onboard for later transmission
• GPS is included for subsequent geometric processing of the data
• Primary receiving station: EROS Dara Center, SD
![Page 44: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/44.jpg)
ETM+ Spectral Bands
![Page 45: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/45.jpg)
Landsat 7 +ETM Spectral Bands
Band Wavelength/ µm
Spectral Location
Principal Applications
1 0.45-0.52
Blue Designed for water body penetration, making it useful for coastal water mapping. Also, useful for soil/vegetation discrimination, forest type mapping and cultural feature identification.
2 0.52-0.60
Green Designed to measure green reflectance peak of vegetation for vegetation discrimination and vigor assessment. Also useful for cultural feature identification
3 0.63-0.69
Red Designed to sense in a chlorophyll absorption region aiding in plant species differentiation. Also useful for cultural identification.
4 0.76-0.90
Near infrared
Useful for determining vegetation stress, vigor, and biomass content, for delineating water bodies, and for soil moisture discrimination.
5 1.55-1.75 Mid-infrared
Indicative of vegetation moisture content and soil moisture. Also useful for differentiation of snow from clouds.
6 10.4-12.5
Thermal infrared
Useful in vegetation stress analysis, soil moisture discrimination, and thermal mapping applications.
7 2.08-2.35 Mid-infrared
Useful for discrimination of mineral and rock types. Also sensitive to vegetation moisture content.
![Page 46: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/46.jpg)
Landsat Resources
• Data acquisition
)http://landsat.usgs.gov/pathrows.php
![Page 47: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/47.jpg)
Enhanced Thematic Mapper Plus (ETM+)
• 8 8-bit bands: bands 1-7 are the same as TM; additional panchromatic band 8, 0.52-0.90 μm
• IFOV 30 x 30m (bands 1-5 and 7), 60 x 60m (band 6), 15 x 15m (band 8); swath width 185 km.
• Images the earth once every 16 days; 1999 to present
![Page 48: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/48.jpg)
Landsat MSS Image Interpretation
• Scale & resolution differences between conventional aerial photos & Landsat images
• Landsat imagery should be viewed as a complementary interpretive tool rather than a replacement for low altitude photography
![Page 49: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/49.jpg)
Landsat MSS Image Interpretation
• Most Landsat MSS images can only be studied in two dimensions
• Effective resolution: 79 m
(30 m on Landsat-3 RBV)
![Page 50: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/50.jpg)
Landsat MSS Image Interpretation
• Due to the line scanning system (one-dimensional relief displacement), Landsat images can be viewed in stereo only in areas of sidelap on adjacent orbit passes.
• Sidelap varies from 85% near the poles to 14% at the equator. Endlap is only 10%.
![Page 51: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/51.jpg)
Landsat MSS Image Interpretation
• Small vertical exaggeration when MSS images are viewed in stereo (extreme altitude vs. base distance between images)
• Base to height ratio: 4x in stereo airphotos, 1.3x to 0.4x in Landsat MSS
• Landsat MSS imagery has been used as a planimetric mapping tool
![Page 52: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/52.jpg)
Landsat MSS Image Interpretation
• The most appropriate band or combination of bands of MSS imagery should be selected for each interpretive use:
• Bands 4 (green) & 5 (red) for detecting cultural features (5 provides higher contrast, 4 greater water penetration)
• Bands 6 & 7 are best for delineating water bodies
• Bands 5 & 7 are best for geologic studies (the largest single use of Landsat MSS data)
![Page 53: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/53.jpg)
Landsat MSS Image Interpretation
• Landsat satellite passes over the same area during daylight hours about 20 times/year.
• Of course, the actual number of times/year a given ground area is imaged depends on the amount of cloud cover, sun angle, and whether the satellite is in operation on any specific pass.
![Page 54: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/54.jpg)
Terra Spacecraft
• Terra is the first of the NASA’s Earth Observing System satellite series. It was launched in December 1999 and activated for science operation on 24 February 2000.
![Page 55: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/55.jpg)
Terra Instruments
• ASTER: Advanced Spaceborne Thermal Emission and Reflection Radiometer
• CERES: Clouds and Earth’s Radiant Energy System
• MISR: Multi-Angle Imaging Spectro-Radiometer • MODIS: Moderate Resolution Imaging
Spectrometer • MOPITT: Measurements of Pollution in the
Troposphere
![Page 56: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/56.jpg)
New Millennium Program
• Earth Observing-1 (EO-1) is the first satellite in NASA's New Millennium Program Earth Observing series
• EO-1 has validated a multispectral instrument that is a significant improvement over the Landsat 7 ETM+ instrument
• EO-1 has validated a hyperspectral land imaging instrument and the unique science that can be performed with hyperspectral data
• EO-1 has validated the ability of a low-spatial/high-spectral resolution imager that can correct systematic errors in the apparent surface reflectances caused by atmospheric effects, primarily water vapor.
![Page 57: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/57.jpg)
Hyperion
• The Hyperion is a high resolution hyperspectral imaging instrument
• The Hyperion images the earth's surface in 220 contiguous spectral bands with high radiometric accuracy, covering the region from 400 nm to 2.5 µm, at a ground resolution of 30 m
![Page 58: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/58.jpg)
Hyperion Sensor Characteristics
• Spatial Resolution: 30 m • Swath Width: 7.75 km • Spectral Channels 220 unique channels. VNIR (70
channels, 356 nm - 1058 nm), SWIR (172 channels, 852 nm - 2577 nm)
• Spectral Bandwidth 10 nm (nominal) • Digitization 12 bits • Signal-to-Noise Ratio (SNR) 161 (550 nm); 147 (700
nm); 110 (1125 nm); 40 (2125 nm)• Primary uses: General earth materials mapping
geology, mining, forestry, agriculture, and environmental management
![Page 59: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/59.jpg)
ALI (Advanced Land Imager)
• The ALI instrument features 10-meter ground resolution in the panchromatic (black-and-white) band (0.480-0.680 microns) and 30-meter ground resolution in its multispectral bands (0.4-2.4 microns)
• It covers seven of the eight bands of the current Landsat
• It is designed to produce images directly comparable to Landsat 7 ETM+, will establish data continuity with previous Landsats
![Page 60: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/60.jpg)
Comparison of Landsat-7 ETM+ and ALI spectral bands and spatial resolutions
ETM+ ALI Band (μm) Resolution (m) Band (μm) Resolution (m) .450 - .515 30 433 - .453 30 .525 - .605 30 .450 - .510 30 .630 - .690 30 .525 - .605 30 .750 - .900 30 .630 - .690 30 1.55 - 1.75 30 .775 - .805 30
10.40 - 12.50 60 .845 - .890 30 2.09 - 2.35 30 1.20 - 1.30 30 .520 - .900 15(pan) 1.55 - 1.75 30
2.08 - 2.35 30 .480 - .680 10(pan)
![Page 61: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/61.jpg)
AC (Atmospheric Corrector)
• The AC instrument provides the first space-based test of an Atmospheric Corrector for increasing the accuracy of surface reflectance estimates.
• The AC enables more precise predictive models to be constructed for remote sensing applications.
• It will provide significant improvements in generating accurate reflectance measurements for land imaging missions.
• It covers the 0.89-1.60 micron wavelength IR band.
![Page 62: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/62.jpg)
![Page 63: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/63.jpg)
![Page 64: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/64.jpg)
EO-1 Sensors
• Hyperion
• ALI (Advanced Land Imager)
• AC (Atmospheric Corrector)
![Page 65: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/65.jpg)
New Millennium Program
• EOS Terra– ASTER
• 15 8-bit (VNIR and SWIR), 12-bit (TIR) bands: 4 VNIR (1 NIR off-nadir); 6 SWIR; 5 TIR
• IFOV 15 x 15m (VNIR), 30 x 30m (SWIR), 90 x 90m (TIR); swath width 60 km.
• Images are not acquired based on researcher scheduling; 1999 to present
– MISR• 4 VNIR bands at 9 different angles• IFOV 275 x 275 m to 1.1 x 1.1 km (depending on view
angle); swath width 360 km.• 9 day global coverage; 1999 to present
![Page 66: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/66.jpg)
Terra Satellite
MODIS
ASTER (TIR)
ASTER (SWIR)
ASTER (VNIR)
MISR
MOPITT
CERES
![Page 67: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/67.jpg)
ASTER Characteristics• Wide Spectral Coverage
• 3 bands in VNIR (0.52 – 0.86 μm)
• 6 bands in SWIR (1.6 – 2.43 μm)
• 5 bands in TIR (8.125 – 11.65 μm)
• High Spatial Resolution• 15m for VNIR bands• 30m for SWIR bands• 90m for TIR bands
• Along-Track Stereo Capability• B/H 0.6• DEM Elevation accuracy:15m
(3σ)• DEM Geolocation accuracy:
50m (3σ)
![Page 68: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/68.jpg)
ASTER consists of 3 subsystems:VNIR, SWIR and TIR.
![Page 69: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/69.jpg)
Comparison of Landsat-7 ETM+ and ALI Spectral Bands and Spatial Resolutions
![Page 70: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/70.jpg)
![Page 71: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/71.jpg)
![Page 72: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/72.jpg)
![Page 73: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/73.jpg)
Landsat 1-3 sensors
• Multispectral Scanner (MSS) – 0.5-0.6 (green), 0.6-0.7 (red), (near IR) at 0.7-0.8,
0.8-1.1m – resolution: 79 m (1-3), 82 m (4-5) – Each MSS scene is covering a 185 x 185 km area – Return Beam Vidicon Camera (RBV) - Landsat 1 and
2 – 0.475-0.575 m (green), 0.58-0.68 m (red), 0.69-
0.83 m (near IR)– Failed within weeks of Landsat 1
![Page 74: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/74.jpg)
Spectral sensitivity of MSS bands
![Page 75: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/75.jpg)
Landsat 4-5 orbital characteristics
• Altitude 705 km
• Coverage cycle 16 days
• Local crossing at about 9:45am • smaller sidelap (7.6% at the equator)
![Page 76: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/76.jpg)
Sun-synchronous orbit of Landsat 4-5
![Page 77: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/77.jpg)
Landsat 4-5 sensors
• Thematic Mapper (TM) – launched with Landsat 4 and 5 – 7 bands, 0.45-12.5m – resolution: 30m except band 6 (thermal IR
band, 120m)
![Page 78: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/78.jpg)
TM spectral bands
![Page 79: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/79.jpg)
Landsat 7
• Launched on 15 April 1999
• Orbit: very similar to Landsat 4-5 – Sun-synchronous, polar – Altitude: 705 km – Repeat cycle: 16 days – Local crossing time: 10:00 am
![Page 80: Characteristics of remote sensing systems. Different kinds of images Panchromatic image True-color image False-color image.](https://reader038.fdocuments.us/reader038/viewer/2022102619/56649d255503460f949fb8ec/html5/thumbnails/80.jpg)
Enhanced Thematic Mapper (ETM+)
• Scene size – 183 km cross-track – 170 km along-track
• Spectral Bands • 8 bands: all TM bands + 1 panchromatic band • Resolution
– Bands 1-5, 7: 30 metres – Band 6: 60 metres – Band 8: 15 metres