[GRASSLIST:7410] Re: ERDAS Atcor vs. i.atcor

[Grit Schuster]

Hi Martin,

I can't tell you anything about the goodness or performance.

I just know that the moduls use different algorithms.
Atcor for ERDAS uses MODTRAN. The Grass module uses 6S.


As far as I know, MODTRAN is quite widely used.

The method to use for an atmospheric correction depends on
different factors:
on the kind of the atmospheric input data, the sensor, the spectral
bands you want to correct and of course on the purpose of your data
analyses.

An interesting document about the atmospheric correction of ASTER data
is provided by the NASA
http://eospso.gsfc.nasa.gov/eos_homepage/for_scientists/atbd/docs/ASTER/atbd-ast-09t.pdf.
I think this gives a good overview about the relevance of the different
parameters used for atmospheric corrections and their influence on the
accuracy of the results.

You could post this topic to the Applied GIS & RS mailing list
(http://www.matox.com/agisrs/).

If you'll find out something, I would quite interested in it :-)

Sorry that I can't tell you more. Hope this helps a bit!

Grit


Martin Wegmann wrote:

> Hello, 
> 
> I wonder if somebody can judge the goodness of performance for the output of  
> ERDAS Atcor (http://www.geosystems.de/atcor/) vs. GRASS i.atcor 
> (http://www.cs.sun.ac.za/~caz/6S/i.atcorr.html). Are their methods comparable 
> at all? I am not experienced in atmospheric correction and hence all the 
> algorithm are rather meaningless to me. 
> 
> Any links, papers, comparisons etc. are welcome, thanks in advance, Martin
> 


-- 
Grit Schuster, Environmental Scientist

Department of Physical Geography
Albert-Ludwigs Univeristy Freiburg
Werderring 4
D-79085 Freiburg

phone: +49-(0)761-2039124
fax: +49-(0)761-203-3596
email: grit.schuster at geographie.uni-freiburg.de
www: http://www.geographie.uni-freiburg.de/ipg/gkgl/gk.htm