How it works
Nine kinds of vision
The simulator covers protanopia, deuteranopia and tritanopia (a missing cone type), their weaker forms protanomaly, deuteranomaly and tritanomaly, and achromatopsia with its partial form.
Each is a 3×3 matrix applied to the colour channels. For an image, every pixel goes through that matrix at working size, up to 2048 px on the long edge.
Reading the result
In image mode, drag the divider to compare the original and the simulated half, or switch to side by side. Download saves the simulated picture as a PNG named after your file.
