Thanks for the reply!
The differences between a computed band and a real band are indeed clear. This is why I used this topic to convert the computed band to a real band, but to no avail.
Surely most computed bands would need the data type to be float, considering computations will involve either division or multiplication by some floating point number. Still I would agree that the data type must be the culprit. I have now set the targetband data type to int16 (i also tried 8). It trips the error a bit further into the processing, but the result is the same: Cannot construct databuffer. Also, 16 bits would not suffice in any calculation more intricate.
What is especially striking to me is that this does not work when I set the expression to simply ‘B2’, set data type to int16 and convert the computedband to a real band. The difference between the two must be incredibly subtle, because for example the ImageInfo shows now differences, yet the error persists.
The suggested command gives the same result. I am using the above example pretty much ‘as is’, so an error in the code seems unlikely to me, but I happily accept any which are pointed out.
Do you have any other suggestions for possible workarounds?
Thanks a lot.
Danny