Hello everyone, i have a question about the NIR band in sentinel 2 because in snap there is a little confusion when i calculate the NDVI or the Savi the snap use automatically the band 8A (vegetation red edge) and dont use the band 8 NIR. so isn’t that rong?
B8A has its center at 864 nm with a bandwidth of 33 nm
B8 has its center at 835 nm with a bandwidth of 145
(values differ a bit between S2A and S2B)
Most studies use the narrower B8A band because they found it more suitable and better comparable to other missions, like Landsat
There are two Sentinel-2A MSI NIR bands and throughout the paper the Sentinel-2A NDVI was always derived using the narrower MSI NIR band 8A (855–875 nm) as it is more comparable to the Landsat-8 OLI NIR band 5 (851–879 nm) (Table 1, Fig. 1).
To achieve the best results for NDVI and NDWI calculation, RED band is chosen as Band 4, NIR band and
SWIR band are selected as Band 8a and Band 11 respectively in Sentinel-2A
This result raises concerns about the MSI NIR band in data harmonization between S-2 MSI and L8 OLI. It also suggests that using B8A is a good option when calculating vegetation indices (e.g. NDVI).
Thank you for the reply and the explication, this exemples are very useful.