SET THE DATE
On the center bridge, select the correct month by sliding the black selector over the month’s initial (e.g. Mid-April).
ACTIVATE THE HOUR RING
Rotate the inner ring 90 degrees so that it is fully open. Twist the center bridge so that the black slider faces the morning or afternoon hours.
READ YOUR SUNDIAL
Hold your sundial on the chord and slowly turn it until a beam of light projects through the small hole onto the inner hour ring.The outer ring is now positioned North/South. The inner ring is parallel to the equator and the bridge is parallel to the earth‘s axis. Thus, you not only have a sundial, but also a model of the earth and a compass. Adjust for daylight-saving time (1 hour). This should go without saying but daylight savings is something man made and we need to adjust for it. If daylight-saving time is in force, add one hour to the sundial reading.
Experts! You chose to visit this part of our site since you want to know more and operate our sundial with the highest precision and accuracy. Please find below a short summary of potential causes impacting the accuracy of your sundial reading:
As you can see in the summary above this point is not too sensitive. Based on our calculations we are seeing a time reading error of around 30 seconds per degree setting error. Make sure to use our latitude search tool and set the latitude accurately as described in Step 1 of our instruction manual.
Our sundial will be about 2 minutes fast for every additional day of setting error (or the other way around). An example: If the sundial shows correct time on May 5, it will be about 10 minutes fast if temporarily set to May 10 and it will be about 10 minutes late if temporarily set to April 30. Carefully follow the instructions at step 2 of our instruction manual to avoid this error source. Tipp: You will see on the middle bridge of your sundial that we divided each months in three boxes representing the beginning, the middle and the end of each month. Use these boxes to increase the precision of your date setting.
It also matters how accurately you read the time of our sundial. When doing so make sure that the light-beam falls exactly on the index line of the inner ring. In case the light point is above or below the index line you can experience a reading error of around +/-8 minutes.
The proper time correction to add or subtract is often taken from an Analemma diagram and varies between -15 to +16 minutes. Failing to account for this phenomenon, can contribute the greatest error in your time reading! To make things easier for you please find a simple time correction table below:
“d” being the day of the months, “m” being the months of the year, values shown in table are in minutes.
Figures are rounded to minutes and are approximate. You can calculate exact adjustments here.
Although we build our sundials with the greatest care and love possible some production variations can occur. We estimate them to be not more than +/-5 minutes and are thriving avoid them all together with every new sundial we produce!
You need to add four minutes to the sundial reading for every degree you live west of the center of your time zone. For every degree you live east of it, subtract four minutes."
Since there is little chance that all errors add up simultaneously - all positive or all negative - we estimate the regular accuracy of our pocket sundial to be better than +/- 10-15 minutes.
Big thanks to Kenneth, a sundials lover from Sweden, who helped us with this summary.