<p>My sundial shows real time until 11am when it will drop behind an hour until sunset. This is in keeping with daylight saving but why does it show real time before 11am? Am I missing something elementary?</p>

CC BY-SA 4.0
2018-09-24T03:53:29.230Z
Can you add a photo of your sundial to your question?
Mike G
CC BY-SA 4.0
2018-09-24T18:24:29.487Z
My suspicion is that your sundial is calibrated for a different latitude, but your description of a sudden drop of an hour , rather than, say, losing 15 minutes *per hour* , doesn't make much sense.
Carl Witthoft
CC BY-SA 4.0
2018-09-24T20:57:53.587Z
Incorrect latitude sounds the most likely explanation if the discrepancy is as large as an hour. You will get up to 16.5 minutes of difference between apparent solar time from the sundial and mean solar time ("clock/watch time") due to the Equation of time (https://en.wikipedia.org/wiki/Equation_of_time)
astrosnapper
CC BY-SA 4.0
2018-09-24T22:35:09.230Z
Is there a number missing from the hour marks on the dial?  (I've seen it in both a thermometer and a 50 ml burette, and it's amazingly easy to overlook)
DJohnM
CC BY-SA 4.0
2020-02-20T15:41:54.597Z
@DJohnM I wanna see photos of those also! ;-)
uhoh
<the-sun>
Erratic Sundial
Spencer Brown
# Erratic Sundial

(Asked by: username_0 on 2018-09-24)

My sundial shows real time until 11am when it will drop behind an hour until sunset. This is in keeping with daylight saving but why does it show real time before 11am? Am I missing something elementary?

**Tags:** the-sun

> **Comments:**
> **username_1**: Can you add a photo of your sundial to your question?  
> **username_2**: My suspicion is that your sundial is calibrated for a different latitude, but your description of a sudden drop of an hour , rather than, say, losing 15 minutes *per hour* , doesn't make much sense.  
> **username_3**: Incorrect latitude sounds the most likely explanation if the discrepancy is as large as an hour. You will get up to 16.5 minutes of difference between apparent solar time from the sundial and mean solar time ("clock/watch time") due to the Equation of time (https://en.wikipedia.org/wiki/Equation_of_time)  
> **username_4**: Is there a number missing from the hour marks on the dial?  (I've seen it in both a thermometer and a 50 ml burette, and it's amazingly easy to overlook)  
> **username_5**: @username_4 I wanna see photos of those also! ;-)  

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## 0 answers

