I like to use Photo Mechanic especially for keywording for German picture agencies and photographers. For that reason I've set up a thesaurus in German and English containing 22.500 hierarchically organized keyword terms and approximately the three times the amount of synonyms. For the better understanding I give you an example in English:
keyword path: sport / workout / muscle exercises / body building
synonyms: sport: sports / workout: work out; exercising; working out; exercise; work-out; exercises; work-outs / muscle exercises: muscle exercise / body building: bodybuilding
My questions are: How do I have to build up the thesaurus (format and structure) to have it correctly loaded into photo mechanic? Are there limits for photo mechanic in number of terms, number of hierarchy levels, number of syononyms? Is it possible to have the German special characters ä, ö, ü and ß correctly integrated?
If you're going to add a lot of terms at once, using a text editor will be the fastest way. You will have to use a text editor that can read and write text files in the UTF-8 Unicode format. As long as you keep the file in UTF-8, any character is possible, including the special characters you mentioned. There is no limit to the number of terms, synonyms, or depth of the hierarchy.
To get you started, I would use the "Save" button in the Structured Keywords panel to save the sample set out to a text file of your choosing. That way you can see how the data is organized. The format is fairly simple. Tabs control the depth of the hierarchy. Terms are just plain text. Categories are surrounded by '[' and ']', and Synonyms are surrounded by '{' and '}' and should be at the same level as the terms they are synonymous with.
When you're done adding your terms, save the file out as UTF-8 format and then use the "Load" button in the Structured Keywords panel to see the results.
There are free UTF-8 capable text editors for both Windows and Mac OS X. For Windows I recommend Notepad2.exe and on Mac OS X I recommend TextWrangler. A Google search will find you download links for each of these applications.
HTH,
-Kirk