Sen2Cor vs Sentinel Level-2A

Hi, what are the advantages of using Sentinel Level-1C and doing Sen2Cor self-correction instead of Sentinel Level-2A download? Is it possible to check somewhere on what parameters the correction was made in Sen2Cor?

  1. Downloadable S2 L2A is still quite new, until a few weeks/months ago you had no choice than to Sen2Cor process the L1C data yourself.
    I didn’t check (hence don’t know), whether L2A is available for the dates before the “operational” L2A release, maybe you still have to L2-process the “old” data yourself.

  2. Running Sen2Cor yourself, you can chose/adapt the processing parameters, while L2A is processed with a default set (whether that set is fixed or changes with, e.g. geographic region or season, I don’t know).

  3. With expert knowledge, you can modify/adapt Sen2Cor even further to your needs (e.g. replacing internal look-up-tables).

So, it mostly gives you freedom and control.

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Hi Tssmiler,
Using the Sen2Cor on your own ensures that you process your data with the newest version of the algorithm (assuming you keep it up to date of course). Implementation of a new Sen2Cor processor into the Sentinel Level-2A collection processing chain takes time, and also it takes additional time for the old data to be reprocessed. At least that was my experience from the last year.
As far as I remember, it is possible to check the version of the processor being used in the ESA-processing chain in the 2A metadata file. If not, this piece of information should be on the ESA website (I remember digging it out).
Of course, depending on your application, use of the most up-to-date Sen2Cor might not be so crucial, but personally I prefer to do the processing in-house. Also because, as jmendrok has mentioned, you have a complete control of all the parameters for topographic and atmospheric corrections, just to name a few.

I hope it helps.