Sunreach
Why sunrise time isn't when the sun reaches you
The sunrise time on your phone assumes a flat sea-level horizon. In the mountains the sun reaches you when it clears the ridge, often more than an hour later.
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How sunlight, terrain and the time of day work together.
Golden hour in the mountains: when the low sun actually reaches you
Golden hour happens in the sky every day, but in a valley the warm low sun often never reaches the ground. The 6° rule, with Bovec and the Soča gorge as examples.
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How to calculate golden hour: times by latitude and season
The definition, the maths in one paragraph, golden and blue hour tables for six cities, and the one thing every golden hour calculator leaves out.
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How to use a sun path planner for photography
Pick the camera position, check whether the light reaches it, and understand the difference between a sunlit viewpoint and a sunlit subject.
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Plan drone filming around sunlight and shadows
Choose a light window for an aerial composition, preview the view from a chosen height and explore how the camera and daylight change together.
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Find sun or shade in a city with 3D buildings
Buildings decide the light in a city. Turn the 3D city view to the minute you plan and see which side of the street is lit.
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Peak light and valley fog: when is it worth going?
Which summits catch the pink light after sunset, for how long, and whether a cloud bank will kill it. Plus the mornings a valley fills with fog.
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What Kp do you need to see the aurora from your spot?
From any Kp in Tromsø to Kp 4.9 in London and Kp 7.3 in the Alps: what decides it, and how far ahead you can know.
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What time is the aurora strongest? Magnetic midnight, place by place
Magnetic midnight is 23:28 in Edinburgh and 02:19 in Yellowknife. Away from it the oval pulls back: about 0.8 Kp more at dusk, 1.8 at dawn.
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How to read an aurora forecast: Kp, Bz, solar wind and the OVATION map
Kp says how far south the aurora reaches. Bz says whether it will brighten in the next hour. The map says where it is now. Read them in that order.
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