I am trying to understand a weird issue here and I may be barking up the wrong tree as it may be an Element84 API problem. However, there is a lot of expertise in these forums, so I thought I’d give it a shot.
I appreciate your time.
I have been downloading S2 images over Denmark which are subsequently cut down to farm field polygons from August 2021 to April 2022 (Fully Python based). Currently these are images that are being provided by the Element84 API. However, I have noticed that there seem to be double data occurances for images captured in 2021, but not in 2022. Below I have attached an example of some field level images:
Not only are there double occurances, but there also seem to be differences between the “duplicates”. Some occur darker/brighter and for the snow covered images one seems to be more blue.
I have double checked on Sentinel-hub EO browser to understand the tiling and the fields do reside inside an area of 4 tiles overlapping as seen in the image below:
But if that was the cause of the problem, there should be 4 occurances and it still does not explain the issue of why it happens in 2021 and not in 2022.
When I check Sentinel-hub again for the February 28th occurance, it looks identical:
So according to Sentinel-hub the data should be similar.
What am I missing here? Is it an E84 API issue? Is there a general change in data between 2021/2022 that just is not reflected differently on Sentinel-hub?
Appreciate any input.
Thank you for your time.