Continue to play with the camera

still have the triangular dots, but did find an imagemagick command to adjust the colours

here is a shot of page 37 from The Art of Color by Johannes Itten.
initial raw image with the greenish tone

then

convert input.jpg \( +clone -channel RGB -equalize \) -average output.jpg

(all on one line)

and we get:

Looks closer to what it should.

still todo:

focus
the little dots

update: a few more recognizable brands with their colours; I think it is a bit too dark blue for the Tetley box..