Always indicate the moon and its phase if it is observable. Note the orientation of this polarization relative to the plane formed by pointing to the part of the sky being observed and pointing to the sun. Check your sun shadow. Take your hand and bring it close to the ground and the region immediately beneath the hand becomes darker. We have as many shadows as there are sources of light.
Daylight includes the sun, skylight and reflections off nearby objects.
During cloudy days we still have sky shadows. The material used to form plastic safety seals around the lids of many food products may fluoresce under ultra violet light. This can be tested by visually examining the material under inside incandescent light illumination, and then under outside daylight illumination. If outside they show a faint blue glow, they are fluorescent and may be used to detect soft UV light. Check the UV of inside fluorescent lights.