A sign with display lighting or an electronic sign panel shall be constructed so that it does not glare upon adjoining property. All measurements of light intensity from a billboard shall be taken at a height of six feet at the yard setback line on parcels that adjoin the parcel where the billboard is located or at a building on parcels that adjoin the parcel where the billboard is located, if a then-existing building is closer to the deed line than the yard setback identified in that particular zoning district. When the lot where the billboard is located adjoins commercial or industrial zoning districts, the light intensity, at its brightest, shall not exceed 3.0 footcandles at the measuring point. When the lot where the sign is located adjoins a residential zoning district, the light intensity, at its brightest, shall not exceed 1.0 footcandle at the measuring point.