RGB colour mode is the colour rendered by electronic display, while CMYK colour mode is the colour rendered by mixing the inks in the printer. They are both colours that are rendered through a perceived intervention. 

But the colours that are artificially interfered with are not the same as natural colours, so how do natural colours interact with the human eye? What definition does each person have of a named colour?

Yuki focus on blue, the colour that makes up the smallest proportion of fruit and vegetables, and for her blue is a vague colour because she believes there are thousands of different colours, it is a colour between red, purple, green and black.

By heating these fruits and vegetables, some of them appear in a completely different colour than they did before the heating, and even some of them have different names for the colour in different language systems. Yuki uses handmade paper for colouring.

Aubergine skins that have been cooked for a long time and then applied to paper take on a very light blue-green colour.

Fresh blueberries are dark purple or dark blue, but when heated they appear purplish-red. The colour is different when applied to different paper materials. On A4 paper it appears dark blue-green, on harder paper it appears light blue.

"Red Cabbage" is red in English, but in Chinese it is translated as "Purple Cabbage". And it does appear blue when heated.

Fresh black grapes appear black, but when heated they turn purplish red.

Fresh blue-black blackberries turn purple when heated.