Landsat 5 tm reflectance product images are delivered as signed 16 bit images, why is this preferred to unsigned 8 bit that the DN's are stored as level 1 products for the same satellite? Look at table 6-1 on page 19 of the following document:

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    It may be nice to possibly edit your question to include a link to a Landsat page showing this usage... it's likely not 100% vital, but it provides background for casual users wishing to understand your question better (also, you could consider even adding links/reasoning about signed/unsigned ints... I certainly understand why you ask the question, but because this community is for people interested in earth sciences, it may see folks who aren't as computer-oriented, and so could make the question more approachable/wide-reaching) :-) Wish I knew the answer, it's an interesting question – JeopardyTempest Nov 6 at 10:39
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    Not knowing a ton about the topic, I wonder if maybe they use -999 or such to indicate some kind of errors or extra information? And after all... the data types are the same size aren't they? If so, perhaps it was just a random choice of the more typical int, overlooking the "clearer" option of making it unsigned? – JeopardyTempest Nov 6 at 10:41
  • Oh, I guess they'd use 8 bit unsigned you're saying? – JeopardyTempest Nov 6 at 10:43
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    Thanks, added in some edits as you suggested. – Chayan Lahiri Nov 7 at 0:09
  • The data is delivered as files and a file format, rather than raw data. What formats are used? – com.prehensible Nov 10 at 9:36

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