About Adapting Conrad’s Prose to Film

On the example of Apocalypse Now by F. F. Coppola, Heart of Darkness by N. Roeg, The Duellists by R. Scott, The Shadow Line by A. Wajda, and Secret Sharer by P. Fudakowski, I would like to show that Joseph Conrad’s prose is a cinematic trap for film directors. This being so, I attempt to answer the question as to why it is so difficult to make a film of something that is so cinematic, when it is being read, and why film adaptations that closely follow Conrad’s narratives are less Conradian than films which are “merely” inspired by Conrad’s works.