Bobby Shafto | North Coronado May 18th @bobshafto | Uploaded May 2024 | Updated October 2024, 1 hour ago.
Same details as previous day. Similar conditions, but clearer. No noticeable inferior mirage. Can see tip of "spur" at south (left) end of the island barely poking up over the horizon.

$Show How to Calculate This Without Presuming R This is from my archives: a ship sighting just after sunset in November 2018. This looks kind of like a submarine; but its not. Its a US guided missile destroyer with several meters of its hull seemingly eclipsed near the horizon, as if it appeared to be sinking. Its not sinking, of course. But theres about 0.02° (or 1.2 minutes of arc) of ship between its waterline and its flight deck) that is missing from view. Do not presume the earth is spherical. Do not refer to a globe curvature calculator. Instead, show and explain how to use the principles of perspective, angular compression, optics, diffraction limits, Rayleigh criterion, lensing, camera zoom factor, refraction, mirage, sea state, or whatever else you think is a factor to arrive at a figure approximately equal to the amount of ship thats appears to be obscured from view. If you need additional details for calculations or formulas, just ask: - Date/Time? - Ships distance? - Camera height? Location coordinates? - Sea surface temperature? - Air temperature (at camera location)? - Barometric pressure; relative humidity? - Significant wave heights? Tide data? - Camera optics (aperture size, focal length)? - Camera sensor data (size, type, resolution)? - Ship details (length, height above waterline, identification)?$

Experimenting with Pablosdogs Mesa Lane Images

Perspective, Eye-Level and Vanishing Points

North Coronado May 18th @bobshafto