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[This page is under construction]

IKONOS is a commercial earth observation satellite. Details about the sensor are provided at Digital Globe's IKONOS Data Sheet

Availability (Sample Data)

Pre-Processing Overview

Typically, multispectral satellite data are converted into physical quantities such as Radiance or Reflectance before they are subjected in multispectral analysis techniques (image interpretation, band arithmetic, vegetation indices, matrix transformations, etc.). The latter can be differentiated in Top of Atmosphere Reflectance (ToAR) which does not account for atmospheric effects (absorption or scattering) and in Top of Canopy Reflectance (ToCR) which introduces a "correction" for atmospheric effects.

In order to derive Reflectance values, likewise as with remotely sensed data acquired by other sensors, IKONOS raw image digital numbers (DNs) need to be converted to at-sensor spectral Radiance values. At-sensor spectral Radiance values are an important input for the equation to derive Reflectance values.

Converting DNs to at-sensor Radiance can be done by using the following equation:

Converting to Top of Atmosphere Reflectance, also referred to as Planetary Reflectance, can be done by using the following equation:

Failed to parse (syntax error): {\displaystyle \rho_p = \frac{\pi * L\lambda * d^2}{ESUN\lambda * cos(θ_S)}}


  • - Unitless Planetary Reflectance
  • - mathematical constant (3.14159265358)
  • spectral Radiance at the sensor's aperture, from equation... ToADD
  • - Earth-Sun distance in astronomical units, interpolated values
  • - Mean solar exoatmospheric irradiance(s) (W/m2/μm), interpolated values
  • Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle cos(θ_s)} - Solar zenith angle, from the image acquisition's metadata

Modules overview




Importing data


Color composites


Pan Sharpening


Calculate Planetary Reflectance


References / Sources

See also


Atmospheric correction

See Atmospheric correction

IKONOS Image classification

See Image classification