Our golden-hour convention
Morning golden hour runs from sunrise to solar-center altitude +6 degrees. Evening golden hour runs from +6 degrees down to sunset. Photography communities use different conventions, so the threshold is shown rather than presented as a universal definition.
Our blue-hour convention
Morning blue hour is the interval from −6 to −4 degrees. Evening blue hour is the interval from −4 to −6 degrees. At high latitudes the required crossings may be absent, in which case an incomplete window is not invented.
What the calculation cannot predict
Cloud cover, haze, foreground shadows and obstructions affect color and contrast. The timing helps you prepare; it cannot promise a vivid sunset. Use your actual coordinates and local weather information for field planning.