we have a timetable on our website for Fomapan films.
Rodinal is slightly higher concentrated as R09.
R09 from Foma is actually made by Foma and R09 from Calbe made by Calbe.
The recipees where made available to all firms in the former eastern block by their system of knowledge transfer and process organisation.
We usually suggest to transfer Rodinal times to R09 times or vice versa by using the 1+50 diluton of Rodinal together with the 1+40 time of R09.
Personally I would suggest A49 1+2 for Fomapan 100.
It gives less grain yet effective 100 ASA speed.