Editing Talk:482: Height
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;Conversion of pixels to height | ;Conversion of pixels to height | ||
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− | + | height<sub>final</sub> = height<sub>initial</sub> * factor | |
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− | + | pixels = Log<sub>base</sub>(height) | |
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− | + | pixels<sub>final</sub> = Log<sub>base</sub>(height<sub>initial</sub> * factor) = Log<sub>base</sub>(initial) + Log<sub>base</sub>(factor) | |
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+ | Therefore vertical distance on this graph represents a multiplicative change in true distance from the starting point of measure. | ||
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+ | pixels<sub>delta</sub> = pixels<sub>final</sub> - pixels<sub>initial</sub> = Log<sub>base</sub>(factor) | ||
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+ | Therefore a vertical change in pixels always represents the same multiplicative factor. | ||
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+ | base<sup>pixels<sub>delta</sub></sup> = factor | ||
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+ | base = factor<sup>1/pixels<sub>delta</sub></sup> | ||
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+ | From the diagram it appears that 550 pixels represents a change of x*1000000. | ||
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+ | 1000000<sub>meters</sub><sup>1/550<sub>pixels</sub></sup> = base | ||
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+ | 1000000<sup>1/550<sup>pixels<sub>delta</sub></sup></sup> = 1000000<sup>pixels<sub>delta</sub>/550</sup> = factor | ||
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+ | The following can be used as an equation to estimate and validate the heights on the diagram, where height<sub>initial</sub> is the height of the reference point in meters, pixels<sub>delta</sub> is the vertical change in distance in pixels, and is positive if height increases and negative if height decreases. | ||
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+ | height<sub>final</sub> = height<sub>initial</sub> * 1000000<sup>pixels<sub>delta</sub>/550</sup> | ||
[[Special:Contributions/108.162.216.149|108.162.216.149]] 12:40, 30 September 2014 (UTC) | [[Special:Contributions/108.162.216.149|108.162.216.149]] 12:40, 30 September 2014 (UTC) |