I have a big image (3.7 GB) that is the results of the stitching of several hundreds of microscope pictures. At the end of the stiching procedure I got three files contaning the three different color layer of the composite picture. Each of these is a TIFF 16-bit image. 
If I open the three layers as a sequence (I have uploaded a screenshot of this picture: three-layers.png) I can try to convert it in a single layer RGB image, via Image->Color->Stack to RGB. I get a color picture, but that is mess up (see rgb-merge.png). 
If I export this image as a png, for example, and I open it with Gimp, it looks normal. So there is a problem somewhere with the visualiziation of this image. 

Thanks for helping.

Antonio

Information about your version of Java:

  os.arch => amd64
  os.name => Windows 7
  os.version => 6.1
  java.version => 1.6.0_24
  java.vendor => Sun Microsystems Inc.
  java.runtime.name => Java(TM) SE Runtime Environment
  java.runtime.version => 1.6.0_24-b07
  java.vm.name => Java HotSpot(TM) 64-Bit Server VM
  java.vm.version => 19.1-b02
  java.vm.vendor => Sun Microsystems Inc.
  java.vm.info => mixed mode
  java.awt.graphicsenv => sun.awt.Win32GraphicsEnvironment
  java.specification.name => Java Platform API Specification
  java.specification.version => 1.6
  sun.cpu.endian => little
  sun.desktop => windows
  file.separator => \

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  JAVA_HOME is set to: C:\Users\JRCITU~1\Desktop\Fiji.app/java/win64/jdk1.6.0_24//jre
  imagej.dir => C:\Users\JRCITU~1\Desktop\Fiji.app

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