| | 1 | === I have no ground truth reflectance data - how can I convert my radiance to reflectance? === |
| | 2 | |
| | 3 | '''A:'''[[BR]] |
| | 4 | The absence of ground reflectance data from your site means that an empirical method of atmospheric correction will not be possible (unless some of surfaces at you site are very spectrally stable in which case spectra could be measured from them after the data collection date ~ however, even then, there is some debate as to the true effectiveness of pseudo-invariant spectral targets). |
| | 5 | |
| | 6 | The best remaining option is to use one of the radiative transfer based atmospheric correction methods. Some of the standard methods that are available in common image processing software allow an output in reflectance, albeit dependent on the performance of the model. Two such models are: FLAASH (a tool in ENVI), and ATCOR4. |