Mosaicing Seadas produced OLCI L2 files with gpt

I am trying to Mosaic a set of OLCI L2 files made with NASA’s L2gen. I have done this in batch for L2 files produced with C2RCC. POLYMER and OCsmart, however I seem to have an issue with L2gen files.
I believe it has to do with the fact the L2gen files stores the geolocation data as a variable and each variable with size of lines and pixels per lines. I am attaching an example file an example for th L2gen netcdf file and my xml file that has worked for other atmospheric correction processors.

Appreciate any help.
Jonathan Sherman
mosaic_l2gen_PB.xml (2.3 KB) (692.4 KB)

The source product you have provided is almost complete out of your defined bounds and has only a few valid pixels. But I think this is only an example.
But when using your settings, I see the small overlapping part in the mosaic.

What kind of an issue do you refer to.
One issue I see is at the edge of the source image. Even better visible when adapting the mosaic area to the input scene.

Up to a certain distant the closest pixel is searched, and this leads to a duplication of pixels. The searching is necessary for the pixel-based geocoding.
This has been observed before.

The second one contains a workaround. But this would mean that you need to do the l2gen processing again.
You cut out a larger area, do the l2gen processing on them, and then reprojecting the scenes and cut out the final region.

Thank you Marco. Sorry I posted a semi-complete question and yes you are right the file I added was an example, but should have added on with more significant overlap. To make this more clear I am attching the error message I get once running the code. For each file that is included in the mosaic and is read, the following is outputted:

INFO: org.esa.snap.core.gpf.operators.tooladapter.ToolAdapterIO: Initializing external tool adapters
INFO: org.esa.snap.core.util.EngineVersionCheckActivator: Please check regularly for new updates for the best SNAP experience.
Executing processing graph
INFO: org.hsqldb.persist.Logger: dataFileCache open start

Error: [NodeId: Mosaic] Operator 'MosaicOp': Unknown element 'elevatioodelName'

Hope this make my issue more clear.

Okay, this makes it easy.

Have you carefully read the unknown element? “elevatioodelName” :slight_smile:
Two letters got lost in your XML file. It should be “elevationModelName”.

Thank you so much! my brain completely glossed over that :roll_eyes:

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