NDVI-images offset when changing from 4326 -> 3067

Hey.

I have a headache with SentinelHub images offset in some parts of Finland.

I send everything to SentinelHub in ESPG 4326. Then i change the format to 3067. My map system is in 3067.

Here is image from southern western Finland. More i move to south and west, more the image gets offset.

Is there anything I can do in SentinelHub settings or any idea where the problem lies?

I use LeafletJS in AngularJs. Yes, it’s rather old project.

Here is a picture of the issue:

Hi,

Reprojecting images sometimes introduce some offset errors. Is there a reason why you are not using EPSG:25835 in your Sentinel Hub Request? Referring to this page, it seems to be identical to 3067.

Perhaps you could try this as your input and output projection into Sentinel Hub and this may reduce the offset error.

It’s not on the supported CRS:s list.

EPSG:25835 is UTM Zone 35N. Sentinel Hub should support all UTM zones.

If I use it in my image post call i get response: “Unsupported CRS value. Check supported values at CRS support”.

Or is there a workaround to it?

I apologise for the confusion, the UTM zone I linked to is based upon ETRS89 whereas the UTM zone projections in Sentinel Hub are based on WGS84.

The correct EPSG you can try is: 25835. Hope that this helps to solve your offset issues.

Thank you, I got the process API to fetch images with EPSG:32635. There is a slight offset still on the image. I think it’s a bit better now, though.

For some reason I can’t put the bounding box on the API call with geometry. get this error: ‘TypeError: Cannot read properties of undefined (reading ‘opengisUrl’)’.

Can i use the EPSG:32635 bounding box in the script? These are my params which work:

const getMapParams = {
crs: ‘EPSG:32635’,
fromTime,
toTime,
width,
height,
format: sentinelHub.MimeTypes.PNG,
geometry,
}

I’m just wondering if I could get better accuracy if I send the bounding box in the API call.

Ah after I posted this i see you mentioned 25835, not 32635.

However, issue seems to remain the same with it.

Hi, can you try making the same request but using Process API? You can quickly do this in Request Builder where you can specify your AOI in whichever CRS you require (as long as it is compatible with Sentinel Hub).

Then we can compare the offset. it would be helpful if you could visualise this too.

Ok returned to this issue now.

Request builder was helpful, it seems I have been calculating width and height wrong. Thank you for your assistanse.

This topic was automatically closed 60 days after the last reply. New replies are no longer allowed.