how to force reading 3D TIFF as 8-bit?

[lynx . abraxas]

Dear mailinglist members,


Using
imread ("some3D.tif", "Index", "all")
for  an  image  that  is  padded with zeros always gives me a binary 3d matrix
eventhough there are values above 1 in sucessive slices. If I do not read  all
slices  but use Index to start reading at the first slice that contains values
above 1 I get the correct matrix.
Now I wonder if there is a way to force reading 8-bit. Also
info= imfinfo (arg_list{1})
info.BitDepth
behaves the same on either gentoo or Debian.
If not, what other formats are recommended for reading (big) 3D images?

Many thanks for any help or hints
Lynx