I have now plugged the iMac into my Mac Mini in Target Disc mode and am able to complete the initial run through of Testdisk.Now the problem... I really don't know how to proceed! I apologize for my ignorance but I am not sure if I should be trying to Fix A Boot Sector, Recover a Partition or what and in what order. I have looked at every example I can find but none of them look anything like what I am getting at least once you get past the first few levels of menus. I really don't want to mess things up more than they are by trying something inappropriate. The Drive was partitioned however it came from the factory - Testdisk identifies it as EFI GPT. I believe that it may have another partition that was added by a (pre-Boot Camp) Windows emulation program that I used to use but other than that just the one partition.
Basically, I'm throwing myself on the mercy of the experts and hoping someone can at least get me started in the right direction. I have attached the Testdisk log file as a Zip.
My thanks in advance to anyone who can help.
Kevin King