Sentinel 2 Preprocessing Error

Hello can someone help me with the following error? it tackles the expression found in band maths mask (check the pic please). Also i cannot edit the info in the bandmaths_mask tab (this is were the error is appearing). Also no source bands are appearing idk why in both subset_reflectance and subset_sun_zenith.
I am also using this xml file sentinel_2_pre_processing.xml (6.3 KB)

i am also following this tutorial

Appreciate your help thank you

Can you check in line 61 if “Subset_reflectance” exists? I think your should use the “Subset” as your source, right?

can you specify line 61 in what or what should i fix exactly step by step\ please? I started using SNAP few days ago so I am just a beginner hahaha :slight_smile:
thank you

Your node “Write_reflectance” is saving a file which input is “Subset_reflectance”, but this inputs is not really generated until the following node (called indeed “Subset_reflectance”), fed by “Subset”. Maybe you have to change the order of the nodes.

What order do you think I should change?? Also do you have another sentinel_2_preprocessing xml file i can use that might work? Sorry for the many questions
Thanks in advance

Is this graph coming from the Sen ET plugin?

it is coming from Tools/Graph Builder. I need it to later get the daily ET estimates. But i got the sentinel_2_pre_processing.xml from people posting this xml file here on the forum as i couldnt find mine as described below.

You can see here there is no such xml file. I even checked in each folder and no sentinel_2_pre_processing.xml.

It the graph is from the Sen ET, do not change it. It should work fine with S2 L2A data.
Which type of image are you using?

I managed to find the sentinel_2_pre_processing.xml file on my pc

but im still receiving this error and I cant edit the info in BandMaths_mask.


Also no bands are appearing in the “source bands” part.

Have you dowloaded the S2 L2A image yourself? Have you indicate which one you want to process in the read label? I am not able to see it.

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yes i downloaded it from Copernicus Open Access Hub. Yes i added it in the read label

You have dowloaded L1C (TOA reflectance), you need L2A ( BOA reflectances)

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oh okay will try and update you. Sorry for the questions as I am still new here lol.

I am trying to download an L2A but it seems the image/product is offline. Do you know when will it be online or when can I download it normally?

Only the last view month are always online.
But as the message says the product will be retrieved and will be made online.
It can take up to 24 hours till it is online. Or more but often less.

You can also try some other data provider.

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Hello again.
I downloaded the L2A and now i have a different error (error: org.esa.snap.core.gpf.graph.graphexception) but still the same problem (cant edit info in BandMaths_mask and no bands are appearing in source bands).