Sensor Map: Charts: one extreme value

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Example: Sensor 3149, today, 16.6.2017.
second chart, "Last 24 hours"

The last values where between 0 and 15 µg.
But one PM10 value was more than 2k. Doesn't matter, messure was wrong.
BUT: The Chart "last 24 hours" uses this wrong 2k value for max. So the normal values between 0 and 15
Aren't displayed well because of one wrong value.

The goal should be to determine such wrong values and perhaps cut them to display the correct
values correctly.

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Some hours later:
The values are with 4 and 4 ok. The "24h floating" graph still suffers on that missmessurement
the "Last 24 hours" still suppress the low values because of the >2k value yesterday.

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Would it be possible to implement zoom (+/-) buttons at the "Last 24 hours" charts?
So the interesting low values could be seen.