Could be that his library sends 1.6 to the scanner and the scanner rounds to the closest supported value, it wouldn’t be unheard of.
Or you could be sending another triplet that resets the frame.
list all of the triplets you send in order, and if you’d like me to test this in my code then install a kodak i30 in simulation mode and test your code again. this way we’d be looking at the same triplets on the same hardware with different librarys.
and the whole/fraction thing – it’s how you send twain fix32 values, also common.
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