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                         HDR being High dynamic range imaging, that is the ability to combine several pictures of the same image/subject but taken with different exposure in order to create a more impressive result.  | 
                
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                                     Read the following review to find out: http://www.linuxlinks.com/article/20100323145610371/HDRImaging.html In short, they are CinePaint and Hugin plus a few more...  | 
                            
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                                     There's a general overview of HDR software on the panotools wiki here: http://wiki.panotools.org/HDR_Software_overview Although it's not Linux specific it does tell you what runs on which platform.  | 
                            
			
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