Is anyone aware of problems or "features" of the Band module ?

I began experimenting with the Band module because I thought that it might
offer a convenient way to scale float data into discrete byte values for the
purposes of utilizing "delayed" colors. It did work nicely for that, but I see
that it has the additional effect of eliminating interpolation between colors
in the rendering of scattered points. For my purposes, I consider that a big
bonus ! However, I am finding that the results are not perfect in every case.
In particular, when I band byte data (scaling not required, but I'm banding it
so that it looks like the other data sets when rendered), there are regions
within the image that are black (as if no data). It looks to me like there is
some kind of polygon filling algorithm run amok. The regions that are colored
(not black) look fine (similar to the original, unbanded data), but they are
outlined with the color that would, if correct, correspond to the adjacent,
black areas. This scenario hints at an algorithm that tries to estimate a
polygon but closes it inward (forming an outline around an existing "blob"
rather than outward, to form a new blob.

Strangely, I see no problem with the banded data if it originates as float. Or
maybe the important factor is that the float data has a larger range - the byte
data has values only 0,1,2.

How can I eliminate the black areas ? How does this module work ? I see that
whatever it is doing, it changes the positions/connections somehow (can't later
use ShowPositions !)

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