CRS confusion

snap
#1

Hi,

I simply want to display an S1 and S2 image side by side in SNAP for feature comparison.

An S2 image opens more or less the right way up with rationale geometry, but an S1 image opens in acquisition geometry (as if mirrored). How can I simply reproject the S1 image to match that of the S2 image within SNAP?

If I terrain-correct the S1 image, it then confirms to WGS84, not matching the S2 image. I can find no way to reproject the S2 image to match that of the S1.

Help!

#2

You can choose the Reprojection from the menu Raster / Geometric Operations
Select the S1 as source and select the S2 product as Use CRS of

Iā€™m not sure if you have to do first the terrain correction on the S1 product to retain correct values.

#3

That worked. Thanks marpet.

For information, I did need to terrain-correct the S1 image first.

Thanks again.

#4

you can directly choose the Range Doppler Terrain Correction module on the SAR image. It corrects geometric distortions and projects your data to che chosen Coordinate Reference System. WGS84 is predefined but you can select others as well. The S2 scene is probably in UTM so you can choose UTM (Automatic).

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