4 ms·
Sort of. Your photoreceptors are sensitive to overlapping frequencies, which means they’re not linearly independent and therefore cannot form the basis vectors
by dcrazy 1y ago
Sort of. Your photoreceptors are sensitive to overlapping frequencies, which means they’re not linearly independent and therefore cannot form the basis vectors of a 3D space.
CIE XYZ accounts for this by projecting SML excitations down to a 2D plane (XY) and making the third dimension a color-independent luminosity (Z). Since it’s luminosity-independent, the 2D slice is directly analogous to the color wheel.
- jsmith45 1y agoI'm not sure that it necessarily follows from the overlap they are not linearly independent. As far as I can tell that alone would simply make them non-orthogonal basis vectors. The issue is more that there isn't really any frequency that only stimulates the M cones. There are some that more or less only stimulate the L cones, but as we get bluer, the stimulation curves of the M and L cones mostly converge, so we can't really get fully independent M cone stimulation (at least not without tricks like locating specific cones and using lasers to stimulate just the M ones, while missing the L ones.) This does indeed make them not linearly independent, so your overall point still stands.