I don't think that TIF files allow for multiple pages. There are two things we can try:
1. Print multiple DIAdem pages to one page to create a TIF file.
2. Automatically print each DIAdem page to a separate TIF file using a SCRIPT.
Please let me know if one of these solutions would help you and I'll try and figure it out and post a solution for you.
Otmar
Otmar D. Foehner