lichtstralen en -bronnen https://youtu.be/Z0vz_lOpZbI
schaduwen https://www.youtube.com/watch?v=7AdyijS4TJ0
licht en kleur https://www.youtube.com/watch?v=IbtET15Xe-I
spiegelen https://www.youtube.com/watch?v=8I0sdgARdWQ
uv- en ir-straling https://www.youtube.com/watch?v=DFxEgyI5D0E