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Old 12-20-2014, 08:15 PM   #52
Richard W
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Interesting discussion ... seems to me that both, accuracy and precision, are at play here. I cannot eloquently describe either as English is my second language but let me offer this link that defines both in context of cartography and surveying ... Error, Accuracy, and Precision

Looking at two examples provided by Jeffrey brought to the same "resolution" and superimposed ... you cannot miss the fact that they both were rendered from the same data. That data was obtained at certain level of accuracy that matched the desired scale of the original (printed) chart.

This is an example of how precision of the new rendering methods exceed the accuracy of old data. I would refer again to the point number 6 in the link already provided ... 6. Beware of False Precision and False Accuracy!

The simple solution is to render the data with the precision appropriate to the data accuracy. Simply, and some devices and apps are doing that quite well, do not allow to zoom in below what the intended "scale" of the original chart data calls for.

In all other cases, we the users have to be aware of this potential misuse/misinterpretation of chart data. We are still in the transitional period, the surveying methods and cartographic date will only get better with time.
Best ... Richard
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