Invert + Dark Mode = Confusion
Q I use Invert modes on my iPhone to help me see its display. These work correctly when using Light Mode, but fail in Dark Mode. How can I fix that? by DAVE JEWELL
A There’s a common misunderstanding that Dark Mode is another form of inversion. It’s more complex, so interactions with inversion modes result in strange effects. If you find the Smart or Classic Invert modes help you read your iPhone’s display, use them only in Light Mode.
Inversion modes alter colours by optical inversion, which changes everything that’s black to white, and the reverse. Classic Invert applies that to the whole display contents including images, but makes images unintelligible, which Smart Invert addresses by preserving the original colours of those elements which it identifies as images.
Dark Mode aims to do something quite different, in setting dark shades as the background instead of light, using different colours including near-blacks and near-whites according to context. Unlike Invert modes, it can’t change the contents of images or documents which specify colours, so it won’t alter the appearance of images or PDF documents. Some documents are now designed to work with Dark Mode though: this is growing among websites, and is available in rich text (RTF and RTFD) documents too, where Apple has extended the RTF standard with modeless background and foreground colours.
Using both Invert and Dark Mode in combination is therefore asking for two different and conflicting display effects at the same time, and is guaranteed to set them working in opposite directions, resulting in something which is neither inverted nor of dark appearance.