Comment by crumbshot

You can get a delightful spectrum of colour through the filter as well, using the large square emojis:

    ⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜
    ⬜🟥🟧🟨🟩🟦🟪🟫⬛⬜
    ⬜🟧🟨🟩🟦🟪🟫⬛🟥⬜
    ⬜🟨🟩🟦🟪🟫⬛🟥🟧⬜
    ⬜🟩🟦🟪🟫⬛🟥🟧🟨⬜
    ⬜🟦🟪🟫⬛🟥🟧🟨🟩⬜
    ⬜🟪🟫⬛🟥🟧🟨🟩🟦⬜
    ⬜🟫⬛🟥🟧🟨🟩🟦🟪⬜
    ⬜⬛🟥🟧🟨🟩🟦🟪🟫⬜
    ⬜⬜⬜⬜⬜⬜⬜⬜⬜⬜

HN pixel art generator, anyone?