Level of corrected S1 image

Hi,
I am a little confused with the processing levels of Sentinel-1 data. The data downloaded from the ESA website which haven’t gone through the preprocessing workflow is Level 1 data as far as I know but what is the level of the same image after going through the preprocessing workflow? Is it Level 2 now?
Thank you.

Can you please give example and mention the IDs of the data you downloaded?

That’s a real question about terminology.

The definition of processing levels (1 / 2 / 3 / …) and their sub processing flavor depends a bit on each space agency and mission.
There is a kind of generic definition from CEOS and from NASA EOSDIS, both being not fully aligned.
You can read this for instance.
https://labo.obs-mip.fr/multitemp/the-product-names-how-they-work/

So, this depends on your type of preprocessing.
As long as you stay in sensor unit, it is probably still a level 1 product, even if reprojected.

As you can see from the link above the author is using his own definition as well.
I am personally using another one, considering that the L2 are explicitly geophysical measurements, not in sensor unit, and defining sub processing level for Level 1 (1A = SLC, 1B = GRD, 1C = geocoded, 1D = orthorectified).

So I am afraid there is no definitive answer to your question.

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The processing levels do not follow a common specification, as @ghajduch said.
There is just some overlap in the definitions.

Here is the NASA definition: Data Processing Levels | Earthdata (nasa.gov)

For ESA I haven’t found an equivalent.
But for Sentinel-1 it is here: User Guides - Sentinel-1 SAR - Product Types and Processing Levels - Sentinel Online - Sentinel Online
For Sentinel-2 here: User Guides - Sentinel-2 MSI - Processing Levels - Sentinel Online - Sentinel Online (esa.int)