DEM vertical resolution

Dear all,
I have constructed a DEM from sentinel-1 with the Snap application. I want to know the vertical resolution of my product. How I can find it?

you can select “DEM” as an additional output during the Range Doppler Terrain Correction which writes you the SRTM (1Sec at best) into the final product. It will cover elevation_VV (the one from Sentinel-1) and elevation (SRTM). Now you can calculate the difference between both, for example the RMSE between the Sentinel-1 heights and the SRTM heights. But this is just a number which doesn’t tell you much about systematic errors, for example if the quality is bad only in a part of the image.

Thanks. It means somehow to compare the results with SRTM. So, you mean DEM generated from sentinel 1 is always less accurate than SRTM?

in 99% of the cases, SRTM is more accurate, yes.

Sentinel-1 may provide a higher spatial resolution, but is more sensitive to errors from phase decorrelation, short baseline and unwrapping over noise phase areas.

Thank you so much!

have you seen this tutorial? DEM generation with Sentinel-1 - Workflow and challenges

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yes, I did my DEM generation based on this tutorial. Now, I see what you mean. The last page is exactly what you mentioned comparing STRM and DEM generated. Apparently, I skipped that part. Thank you for mentioning that.

happy to hear that.