Changes between Version 1 and Version 2 of Processing/RadiometricCalibration/ATM


Ignore:
Timestamp:
Mar 18, 2008 12:50:34 PM (12 years ago)
Author:
mggr
Comment:

--

Legend:

Unmodified
Added
Removed
Modified
  • Processing/RadiometricCalibration/ATM

    v1 v2  
    1414
    1515For channels 9 and 10 (SW IR), there is a fudge factor - apparently the ATM instrument records lower values when in the air than on the ground.  One should process a flight line and look at dark areas (no cloud, directly under instrument) such as water to get some idea of these, but the dark current is normally ~100-300 lower when flying.  '''does this apply to the max value too?'''
    16 
     16 * For 2007, these offsets were measured (based on averages over large patches of dark water) as:
     17|| '''Band''' || '''Speed''' || '''Measured dark value''' || '''Difference''' ||
     18||  9         || 12.5        || min value 24360           || offset -127      ||
     19|| 10         || 12.5        || min value 24470           || offset -128      ||
     20||  9         || 25          || min value 24310           || offset -177      ||
     21|| 10         || 25          || min value 24470           || offset -128      ||
     22||  9         || 50          || min value 24200           || offset -287      ||
     23|| 10         || 50          || min value 24300           || offset -298      ||
     24 * Used nearest multiple of 10 as the "true" dark value