Does Range-Doppler Terrain Correction quality depend on subset size?

[SDufourBeausejour]

Hello,

Is the quality of terrain correction (TC) using Range-Doppler dependent on subset size?

I ask because I get slightly different pixel values after TC on subsets of different size, but with a common area of interest to me.

In the example below, you can see the size of the subimages and that the smaller subset for a specific pixel yields a value of -21.1 dB, while the same pixel in the larger subset yields -20.6 dB after TC.

Before TC, both subsets have exactly the same pixel values for a given pixel.

Also, I already checked that this isn’t a simple case of the image being shifted one pixel over in one case.

Can someone help me understand what is going on?

Kind regards,

SDB

[ABraun]

I think if you want the exactly same pixel values regardless of the input, you can select nearest neighbor resampling for the source bands in the TC settings.

[SDufourBeausejour]

Thank you, this does give consistent results for different image sizes.