Pre-processing (geometry, atmosphere, clouds)

MAJA 4.5 is now available and compliant with the new Sentinel-2 L1C format

=> UPDATE (Feb 14th 21): the version 4.5.3 is now released and fixes a few minor issues found while testing the first time series of the new L1C format, please upgrade to Maja 4.5.3 ! Following the announcement by ESA of a major product format upgrade for Sentinel-2 by early January 2022, the development team […]

14.02.2022

First validation results with the Lamasquère ROSAS instrument

=> Following its installation in March 2021, our new ROSAS device at Lamasquère has produced a first series of acquisitions over a complete maize crop cycle. The ROSAS system is based on the use of a multi-spectral photometer to carry out angular and spectral measurements of both incident and reflected radiation from the surface. The […]

14.12.2021

Premiers résultats de validation du site ROSAS de Lamasquère

=> Suite à sa mise en place en mars 2021, notre nouveau dispositif ROSAS de Lamasquère a produit une première série d’acquisitions sur un cycle complet de culture de maïs. Le dispositif ROSAS repose sur l’utilisation d’un photomètre multi-spectral pour non seulement réaliser des mesures angulaires et spectrales du rayonnement incident, mais aussi du rayonnement […]

A very green France in July 2021

=> When the summers were hot and dry during the past years, our monthly cloudfree syntheses of surface reflectances from Sentinel-2 for the month of July interested the media. It will probably not be the case in 2021, as France thankfully kept its green colour in July.     Because of the cloud cover that […]

30.08.2021

Une France bien verte en juillet 2021

=> Depuis quelques années, lors de chaque été sec en France, nos synthèses mensuelles de réflectances de surface issues de Sentinel-2 pour le mois de juillet ont été reprises dans les médias. Ce ne sera probablement pas le cas cette année, car la France est restée bien verte en juillet 2021.   En raison de […]

27.08.2021

Oups…

=> Field work rarely goes without a few small hazards. In the case of our new ROSAS station, newly installed a month ago, the hazard unfortunately took the form of a farm machine hitting the mast while tilling the soil on April 15th. The base of the mast twisted under the impact, leaving the structure […]

21.04.2021

Oups…

=> L’acquisition de mesures sur le terrain se passe rarement sans quelques petits aléas. Dans le cas de notre nouvelle station ROSAS fraîchement installée il y a un mois, l’aléa a malheureusement pris la forme d’un engin agricole venu percuter le mât lors d’un travail du sol le 15 avril dernier. La base du mât […]

2 000 downloads for MAJA !

The distribution of MAJA L2A processor, as an  executable software, started in april 1997, but we started counting the number of downloads only since October 2017. The cumulative number of downloads just reached 2000 on April the 2nd 2021. It is on average 1.56 downloads per day, and more than 2 downloads per work day […]

14.04.2021

Can surface reflectance be negative ?

=> Here is a frequently asked question : I noticed, in such L2A product processed by MAJA, that some pixels had negative reflectances, is it normal ? No, it should not happen, but the fact it happens is not entirely surprising, I will explain it below. Unlike negative reflectances, reflectances greater than one can exist, […]

06.04.2021

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