This is a 16-bits/channel composite color image of HeLa cells
with red lysosomes, green mitochondria and red nucleus. Image
courtesy of Tony Collins, creator of the ImageJ for Microscopy
collection of plugins at <http://www.macbiophotonics.ca/imagej/>.

Use the slider under the image to select the channel to be
processed or analyzed. Note how the color of the subtitle 
changes when you switch to a different channel. Use the B&C 
tool (press shift-c) to adjust the brightness and contrast of the 
current channel. Use the Image>Duplicate command to extract
a channel or to convert from a composite image to an ordinary 
stack. Use Image>Color> Convert Stack to RGB to convert to 
24-bit RGB. Use File>Save As>Tiff to save as a 48-bit TIFF.

These two lines of macro code

    info = File.openAsString("");
    setMetadata("Info:"+info);

were used to copy this information from a text file to the image.