Error when TiffPrep

[Kaffir]

I described my Tiff Prep Behaviour here

TIF Scan Prep: Is It Necessary (or Beneficial) for TIF Files that are Already Gamma 2.2?

@nate Yes, this what the Tiff Scan Prep utility currently does. But it is not! Tiff scan prep actually converts to the gamma 1, not gamma 2.2! In my case Tiff scan prep produces the files ending with “gamma-1” And this is the files converted from my linear tiff files with further gamma expansion in terms of imagemagick +gamma .45455 then -gamma 1 where is that point?