53C is a video mode that does not have any attribute limitations, each picture element can have its own color and does not affect neighbor pixels. The smallest element is a 8x8 block that is filled with checkerboard texture. Two colors and extra attributes assigned to a block, which is INK, PAPER, BRIGHT, FLASH. The whole picture consist of 768 blocks. All attribute combinations provide 53 unique averaged colors, hence the format name.

53C graphics examples