Hey there,
haven’t used SNAP for that long so this may be a very simple issue…I am trying to do map algebra on two images, I was trying with “Band math” but that allows me to work on one image only … Can I work with bands from different images on SNAP?
To get around the issue I used the ArcGIS “Raster Calculator”, but SNAP (which is better I think when computing band statistics) won’t read the ArcGIS output correctly (a simple TIFF) 
What can I do?
Thanks!
You don’t give us much information. If your two images are exactly the same size and mapping, SNAP should allow you to use them together in band maths. If that fails, there is a tutorial for SeaDAS 7 (BEAM5) on Sea Surface Temperature Anomalies. Collocation is used to create a file with multiple images all mapped the same way.
You can work with two images but they need to have the same extent.
If they are compatible they are selectable in the Expression Editor window.
Thank you both!
Yes, I was working with two S1 IW and thought they had the same extent but in fact one has 2 columns more! 