Thanks to all for the responses to my problem It seems that I need to convert to sRGB before going into PowerPoint. I normally work in AdobeRGB98 and that would have been embedded in the JPEG files.
One to remember!
Severin
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                    Assoc Professor R Severin Crisp, FIP, CPhys, FAIP
       15 Thomas St, Mount Clarence, Albany, 6330, Western Australia.
                      Phone  (08) 9842 1950   (Int'l +61 8 9842 1950)
                             email  mailto:[EMAIL PROTECTED]
                            Web pages http://www.JennyCrisp.com.au
                               &  http://members.westnet.com.au/Crisp
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