On Fri, Jun 5, 2015 at 12:00 PM, Nikos Alexandris <[email protected]> wrote:
> * Nick Ves <[email protected]> [2015-06-05 11:44:18 +0300]: > > > > > Take note for WV3 [0] digital globe states that > > > > " > > WorldView-3 addresses this problem by being the first commercial imaging > > satellite with an atmospheric sensor as part of its payload. During image > > capture, the WorldView-3 atmospheric sensor is designed to detect the > > presence of clouds, aerosols and water vapor at 31 meter resolution, > > thereby measuring the exact atmospheric conditions corresponding to every > > recorded image [...]. > > > > *DigitalGlobe has developed proprietary algorithms that use these > > atmospheric measurements to normalize WorldView-3 imagery for > consistency*. > > This normalization is called atmospheric compensation, which is > especially > > important for information extraction, such as change detection and > > vegetation analysis because changes > > *due to the atmosphere have been removed*. > > > > " > > > > Which seems to imply that their (of-the-shelf) products are already > > cleaned from any atmospheric artistic. > > > > Further confirmation on that would I think is needed. > > > > > > [0] > > > https://www.digitalglobe.com/sites/default/files/DG_Pixels_to_Products_forWeb.pdf > > > > > Or, maybe it's simply still "new" and calibration wroks are still > on-going? > > I cannot tell if its still new or its yet being callibrated, but they seem to have shown the results of their method (DG - AComp) compared to FLAASH and QUAC methods. Check https://calval.cr.usgs.gov/wordpress/wp-content/uploads/pacifici1.pdf to see if you can make more than me. > See: > < > http://remotesensing.spiedigitallibrary.org/article.aspx?articleid=2300382 > >. > > From you above link there's this exception: "Note that DG plans to implement a WV-3 atmospheric-model-based reflectance correction, taking advantage of the WV-3 aerosol and water vapor CAVIS bands; however, this correction was not available to apply to the data used in this investigation." If that's true and the AComp is not yet implemented to their end-user products I don't think there's a way to atmo correct the images without ground measurements from your part since they haven't published a spectral responses table (as of yet that I am aware of) > Nikos A >
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