Hi forum!
I’m now using TerraSAR SLC data to detect changes. I have 3 images, and I’ve done Clibration, Radiometric terrain flattening and Range Doppler Terrain Correction.
But I got “java.lang.ArrayIndexOutofBoundsException” when I ran the DEM assisted Coregistration.
And another question : for Change Detection application, is it enough to just Create Stack of 2 images?
btw, anmong the 3 images, one is TDX and the other two are TSX
if you want to go sure, you shoul apply the coregistration before terrain correction. This however only works if both images are from the same track (relative orbit). Otherwise you apply Terrain Correction and then merge both product in a stack (Collocation or Create Stack tool)
The DEM-assisted coregistration is probably not the best choice because the spatial resolution of TSX and the DEM (SRTM) is too different.
Thank you for reply!
I think the 3 images are in same track
So maybe I should redo the coregistration and then terrain correction using the Radar->Coregistraion->Coregistration tool, right?
And another question 
, can I subset the images and then do the coregistration? The coregistration is too slow for such a big area. Is there a solution to subset 3 products at the same time?
Thank you in advance!
yes, at best after terrain flattening
If you manage to clip the input products to the (more or less) same extent, you can create the subset as a very first step (this works for stripmap data, but not for Sentinel-1), then calibrate and coregister.
Got it! Thank you for your information! Really help a lot! 
