2
votes
5answers
2k views

Eye sensitivity & Danger signal

Why are danger signal in red, when the eye is most sensitive to yellow-green? You can check luminosity function for more details...
4
votes
1answer
55 views

Vision vs. limiting magnitude

Does anyone know how the acuity of your vision translates to a difference in limiting magnitude? e.g., the kind of answer I'm looking for would be "For each factor of 2 improvement in your vision ...