Digitaltruth Photo

Can you please help re understanding your development time chart. I'm using Fomapan 200, depending on which developer I use I note under the ASA/ISO column there can be different ASA/ISO ratings. I'm currently using Perceptual so that is straight forward and the column shows ASA200. However if I was using Ilfotec DD-X with the Fomapan 200 it shows both 200 and 400 ASA. Why is this?
Thank you.
Mike

ISO incorporates the ASA number and the DIN thus ISO 100/21* represents 100 ASA/ 21* DIN
Hope this helps.