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January 2004
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2004.01.23 20:52 "Re: How to convert MINISBLACK to PHOTOMETRIC_RGB", by Chris Cox
At 2:30 PM -0600 1/23/04, Bob Friesenhahn wrote: > On Fri, 23 Jan 2004, Chris Cox wrote: > > > > > > > I am by no means an authority on the TIFF specification. My interpretation > > > of the file in question is that a sensible application should render the > > > first band in greyscale and ignore the 2nd and 3rd since they are > > > extra samples > > > with no meaning attached. > > > > Or load the 2nd and 3rd channels as alpha (not transparency) channels > > -- as Photoshop does. > > > > It would be incorrect to interpret this image as RGB. > > How does Photoshop treat a second alpha channel? Does it actually get > used for anything? Alpha channels are just alpha channels - they get loaded and the user can do what they want with them. Only transparency (associated alpha) has any special meaning. Chris