Yes, older movies can be converted to 4K. This is typically done through a process called 4K restoration, which involves scanning the original film elements in 4K resolution and then digitally restoring the image. The resulting 4K version of the film can then be released on 4K Blu-ray or streaming services. This process can bring out a lot of detail in the original film, especially in black and white films, and can make the film look better than ever before. However, not all older movies have been converted to 4K, and some may not be suitable for 4K conversion due to the quality of the original film elements or the use of early CGI effects.