Changes between Version 21 and Version 22 of Processing/Py6S_vs_Hyperspectral
- Timestamp:
- Aug 24, 2017, 11:18:08 AM (7 years ago)
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Processing/Py6S_vs_Hyperspectral
v21 v22 60 60 The 6S model simulates at-sensor radiance but the parameters used for the atmosphere (atmospheric profile, AOT) are currently kept the same for all times / regions. Therefore, the values of spectra recorded by the Fenix instrument may differ from those produced by Py6S due to differences in actual atmospheric parameters and those used as input to 6S. 61 61 62 Py6S has several parameters needed to run the model. For this script, ARSF have selected the most convenient ones for our use but do not expect perfect match of the hyperspectral spectra recorded from our sensor against the Py6S. A more detailed explanation about Py6S parameters and [wiki:Processing/Py6S_vs_Hyperspectral/Py6SParameters settings used by ARSF can be found here.]62 Py6S has several parameters needed to run the model. For this script, NERC-ARF have selected the most convenient ones for our use but do not expect perfect match of the hyperspectral spectra recorded from our sensor against the Py6S. A more detailed explanation about Py6S parameters and [wiki:Processing/Py6S_vs_Hyperspectral/Py6SParameters settings used by NERC-ARF can be found here.] 63 63 64 64 Both curves (Fenix and Py6S) should match general features. The peaks and depression (reflecfance-absorption) caused by vegetation have to match and there should be no other spikes on the Fenix spectra that does not match the Py6s. However, note that it is probably to have a spike on some Fenix spectra flightlines on the bands around band 349, close to 900-950 nm. This is caused by the shift on the SWIR bands detected on on October 2014 and those pixels are listed as bad pixels, therefore the spectra recorded by Fenix is correct. You can find a picture illustrating this issue which also suggest the type of spike you have to look for when they are not on the overlapping region.