Terrain Correction_Wrong Map Projection

When I use SRTM 3sec for radarsat 2 (already calibrated in sigma naught), at the end my map projection will be in NAD 27 which is odd! First I went with the default (WGS84(DD)) and another time with UTM 11 Zone/WGS 84.

any suggestion!

I don’t get such a problem. Where is it that you are seeing this nad 27?
If you look at the abstracted metadata of the target product produced, it will have the selected projection

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Yes, in Metadata of SNAP, it shows the correct projection (WGS84(DD)). But when I import it in PCI Geomatica, it shows NAD27 which is odd! In SNAP, Doppler Range Terrain Correction, when we use either SRTM 3sec or External DEM, is there any limitation in the type of map project assigned? I mean can I set it on UTM zone…/WGS84 or WGS84 (DD) or NAD 83/UTM Zone?

Thanks a lot!

ok now that’s a different variable in the problem. How are you exporting the product from SNAP and importing it into PCI? The problem could be there.

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Thanks for your reply. I go with the default.

I don’t know - I’m not a PCI user. It looks like this may be a generic import for reading the raster data but ignoring the metadata.
Try exporting from SNAP to GeoTIFF and then opening the GeoTIFF in PCI without this import.
Note that exporting to GeoTIFF you will also loose the metadata so you may not be able to continue with other processing but you should keep the map projection.

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Good point. Thanks a lot. Just a general question about the type of map projection selected in SNAP, Doppler Range Terrain Correction:
when we use either SRTM 3sec or External DEM, is there any limitation in the type of map project assigned? I mean can I set it on UTM zone…/WGS84 or WGS84 (DD) or NAD 83/UTM Zone?

no, it shouldn’t matter.

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I have a quick question, for the “External Dem” in TC in Snap, do I need an external DEM that covers the entire the SAR image or even partially that would be sufficient to complete the orthorectification? Thanks a lot

Yes, partially covering external DEM can be used. If the DEM only covers part of the scene, the areas without elevation will become no data value.

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So, the SAR image will be orthorectified. But I shouldn’t expect to get the “Local Incidence Angle” for the entire the image for instance?

No, only the pixels where you have an elevation will get orthorectified. You don’t know the geometry of anything else so they can’t be corrected (placed in the correct location).

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So, literally using the partial DEM doesnt complete the orthorec. I had the partially hight resolution Lidar and wanted to avoid using SRTM 3sec and use my own external DEM. However now I have no other choice but to go with SRTM 3sec. Thanks a lot!