Remarks on Colour line that 'There is no such thing as phenomenology, though there are phenomenological problems.' He was content to regard Goethe's observations as a kind of logic or geometry. Wittgenstein took his examples from the Runge letter included in the "Farbenlehre", e.g. "White is the lightest colour", "There cannot be a transparent white", "There cannot be a reddish green", and so on. The logical status of these propositions in Wittgenstein's investigation, including their relation to physics, was discussed in Jonathan Westphal's "Colour: a Philosophical Introduction" (1991). Although "Remarks on Colour" is considered difficult on account of its fragmentation, his last work,
Colour recovery were made in black and white, using still colour photos and/or some educated guesswork to manually choose a colour palette. Conversely, the goal of colour recovery is to reinstate (as closely as possible) the colour signals of programmes originally made in colour as they were first seen. Colour recovery reconstructs the colour information from actual recovered signals and theoretically without depending on guesswork. As of 2018, colour recovery has successfully been applied to episodes of the BBC TV programmes "Doctor Who", "Dad's Army", and "Are You Being Served?". Due to the well-documented practice of wiping, many original videotape recordings of