Some films do have slightly a different emulsion and/or film base between formats. You can tell whether this affects the development by checking the data sheets on the manufacturer web site for their recommended development times to see if they differ between formats. Even if your developer is not listed, you can usually tell whether the emulsion and film base are the same or differ in some manner.(posted 8342 days ago)Whether or not you need to develop to different contrast levels due to different format sizes (or even enlarger light sources) is obviously a separate question.