3 reasons why greyscale is bad for online accessibility | Disability charity Scope UK
1. Colour contrastGreyscale can create problems when it comes to colour contrast. It can be very difficult or impossible for some people with visual impairments to read the information. Websites need to have sufficient contrast with the background. This makes sure the text is readable and other elements are distinguishable. The recommended minimum is 4.5:1 for normal text and 3:1 for large text and other elements.
Issues faced by the visually impaired, following the greyscale changes made by National Rail as a tribute to the DoE.