Golden Hour & Blue Hour Calculator

Path length through air: at 6° elevation, sunlight traverses roughly ten times more atmosphere than at noon, and Rayleigh scattering strips blue wavelengths along the way — what survives is warm (2,500–3,500 K vs noon's 5,500), heavily diffused, and arriving almost horizontally, so textures rake into relief and faces light flatteringly without overhead shadows. Add that the intensity drops to where dynamic range fits in one exposure, and the cliché ('shoot at golden hour') is just optics doing the retoucher's job.

It lasts as long as the sun spends crossing the +6°→−4° elevation band, and that's set by the angle of the sun's path to the horizon: at the equator the path is vertical — the band crosses in ~35 minutes year-round; at 50° latitude the path slants, stretching it to 60–90 minutes; in a Scottish or Scandinavian summer the sun crabs along the horizon and 'hour' becomes an evening. The same geometry makes tropical sunsets feel abrupt and high-latitude ones linger — this tool's output IS that geometry, computed.

Blue hour is the photogenic core of civil twilight: sun between −4° and −6°, sky still bright enough to expose with city lights balanced against it (the architectural and skyline window), deep blue because ozone absorption (the Chappuis bands) tints the residual skylight. Civil twilight runs −0.833° to −6° (you can still work outdoors); nautical to −12° (horizon visible at sea); astronomical to −18° (true darkness). Our twilight calculator maps all three; this one isolates the band photographers book flights for.

Arrive an hour before the window — scouting, framing and tripod time should not spend golden minutes; shoot THROUGH the sequence (the best frame is often 10 minutes into blue hour, after most photographers leave); and mind direction: golden light is directional, so know your azimuth — sun sets where our sun-position tool says, not 'in the west' (it's 30°+ off due west near solstices at mid-latitudes). For cityscapes the money window is the 15 minutes when ambient sky and artificial lights balance — inside blue hour, not after dark.