here for instance, the thread contains links to other relevant material. I am quite puzzled by this Cinestill film: it is based on an ECN-2 film which yields lower contrast and needs a different development agent than regular C-41 films. In order to avoid the low contrast issue the maker rates this ISO 500 film as 800, hoping that push development would fix the contrast. Still, the C-41 process uses CD-4 as color developing agent whereas the ECN-2 process required CD-3. Photoengineer has already commented extensively on this issue.