Look up the "Equation of Time" to make the sundial more accurate. Because of the elliptical orbit of the earth, a time correction has to be added or subtracted from the solar time to read clock time.
this is also good for survival situations , as long as the two sundials are made the same and point in same direction, those two people will be on the exact same time
I'll be building a nicer model from wood and steel in the future. The websites are linked on my website project page. I suppose I cold have used CamStudio to record my desktop, but then I would have had to do a separate voice over track which takes up a lot more production time. I like keep the production of my videos easy. Glad you liked the project! :)
If you know what time it is using a standard clock would it not be easier to lets say at 9 am just line up the shadow to 9 am on your dial? after all the angles for each hour are already mapped out and the angle of the gnomon is already known and set in place on the dial. Let the sun tell you where to line it up.
so wait the angles get smaller near noon and bigger during the morning and evening? On a different video someone did the opposite so I was wondering which was right?
The accordance of the sundial with the "official" time was just coincidence. You didn't mention two substantial points: First: The real local (solar) time differs from the official time zone depending on the longitude. And second: During the course of the year, the real solar time oscillates plusminus a quarter of an hour around the mean time. The first point, you can easily adjust by labeling the dial. The second point is trickier. You can regard to it too. But it worsens the readability.
I want to make a sundial larger than what you've done. I want to make mine out of wood, with the lines and time woodburned in. Do I need t do anythng differently?
No. The same math applies. I prefer armillary spheres however. On armillary spheres, every hour line is exactly 15° from/to the last/next hour line. There is no formula needed. I built mine out of scrap wood for the stand, a 5 gallon bucket lid for the dial and a long screw with a washer on each side and a nut to hold it pretty tightly to a hole drilled in the center of the lid. I also added tick marks at every 10 minute interval. Also, this way, to compensate for Daylight Savings Time, all I have to do is spin the lid (dial) forward or backward 15° (one hour) depending on if it's spring or fall. Mine is HIGHLY accurate. It's only ever off by 15 minutes at the MOST (just like the sundial in the video would be) due to the equation of time (because of the annual solar analemma). Accurate enough to do your daily things (unless you are playing the stock market and a single minute can make a huge difference).
Well, there is the pesky little difficulty of the Earth getting in the way of the Sun during those hours. Perhaps on some parts of a spaceship out away from such a difficulty a shadow, which is rather essential to this kind of dial, might be noted at all times.
A little late but I think all you need to do is google 'declination of _________ (your specific city). It will tell you how many degrees true and magnetic north are apart and which is farther to the left or right. There is also a cite that tells you what the angles are for each line of latitude but can't recall what it is. Good luck.
I never thought of that. This type of sundial wouldn't work on the equator because the gnomon would be flat and not cast a shadow. In this situation you would use an equatorial or vertical dial.If all you have is an horizontal dial you can use the trick of propping up the back with a wedge(at 35 degrees in this example) so that the gnomon points to the north celestial pole . You can also use this trick to adapt a dial that's made for a latitude that's different than yours.
The sun won't be straight up at noon unless you are on the equator and it's an equinox or if you're on a Tropic (of Cancer or Capricorn) and it's a corresponding solstice....or somewhere between the Tropics and it's whatever corresponding day that the sun is directly overhead at noon. If you aren't within the Tropics it'll never happen and even then, technically only for one day.
Lots of stuff missing here. For one thing, there needs to be to 'noons' due to the thickness of the gnome causing it to cast 2 shadows simultaneously. Also, the importance of the difference between magnetic and true north are sort of glossed over here. There are a few other things, as well. Depending on how accurate you want your sundial to be, you might look elsewhere.
Łukasz Cukrovy I saw many videos on such topics; yet in my job as a simple land surveyor, the earth is curving. despite NASA and other professional development of science, There is four corners of the earth! 3 can be seen while the 4th is at gravity point( middle of the earth).
![[UA] NAVI vs MOUZ | BO5 | IEM Rio 2024](http://i.ytimg.com/vi/CMBYk0cbGoA/mqdefault.jpg)
Look up the "Equation of Time" to make the sundial more accurate. Because of the elliptical orbit of the earth, a time correction has to be added or subtracted from the solar time to read clock time.
this is also good for survival situations , as long as the two sundials are made the same and point in same direction, those two people will be on the exact same time
I'll be building a nicer model from wood and steel in the future. The websites are linked on my website project page. I suppose I cold have used CamStudio to record my desktop, but then I would have had to do a separate voice over track which takes up a lot more production time. I like keep the production of my videos easy. Glad you liked the project! :)
Yo how good is ur work?
If you know what time it is using a standard clock would it not be easier to lets say at 9 am just line up the shadow to 9 am on your dial? after all the angles for each hour are already mapped out and the angle of the gnomon is already known and set in place on the dial. Let the sun tell you where to line it up.
so wait the angles get smaller near noon and bigger during the morning and evening? On a different video someone did the opposite so I was wondering which was right?
cool man :D
really helped me on my Science Fair
The accordance of the sundial with the "official" time was just coincidence.
You didn't mention two substantial points:
First: The real local (solar) time differs from the official time zone depending on the longitude.
And second: During the course of the year, the real solar time oscillates plusminus a quarter of an hour around the mean time.
The first point, you can easily adjust by labeling the dial.
The second point is trickier. You can regard to it too. But it worsens the readability.
thank you for the great video
:)) Stick you use to show on whiteboard is so interesting. )))
Ulukbek J. Ikr
Were do you point it from like .. Australia ?
I want to make a sundial larger than what you've done. I want to make mine out of wood, with the lines and time woodburned in. Do I need t do anythng differently?
No. The same math applies. I prefer armillary spheres however. On armillary spheres, every hour line is exactly 15° from/to the last/next hour line. There is no formula needed. I built mine out of scrap wood for the stand, a 5 gallon bucket lid for the dial and a long screw with a washer on each side and a nut to hold it pretty tightly to a hole drilled in the center of the lid. I also added tick marks at every 10 minute interval. Also, this way, to compensate for Daylight Savings Time, all I have to do is spin the lid (dial) forward or backward 15° (one hour) depending on if it's spring or fall. Mine is HIGHLY accurate. It's only ever off by 15 minutes at the MOST (just like the sundial in the video would be) due to the equation of time (because of the annual solar analemma). Accurate enough to do your daily things (unless you are playing the stock market and a single minute can make a huge difference).
Yes. Get a bigger piece of wood.
Does it work with the moon?
Is it possible to build one with the hours 6pm to 6am as well, so that it had all 24 hours.
How would you go about doing this?
So you want a sun dial that works at night ??
Moon dial. LOL
Thank you so much!
Thank you!
What if you didn't have a clock?
THANK YOU!
what drawing program did you use?
Well, there is the pesky little difficulty of the Earth getting in the way of the Sun during those hours. Perhaps on some parts of a spaceship out away from such a difficulty a shadow, which is rather essential to this kind of dial, might be noted at all times.
Is there an international website for getting the estimated value of magnetic declination depending on location coordinates ?
A little late but I think all you need to do is google 'declination of _________ (your specific city). It will tell you how many degrees true and magnetic north are apart and which is farther to the left or right. There is also a cite that tells you what the angles are for each line of latitude but can't recall what it is. Good luck.
How can i get this image
how do you get the dials of philippines?
nico alleje idk
Love me some sundials
Does anyone know how those in ancient times determined the angles needed based upon their lattitude?
They used a carpenter's square/protractor, a string, a plumb bob, a compass (drawing compass. Not a directional compass) and geometry.
How about 0 degree latitude? and negative latitude?
I never thought of that. This type of sundial wouldn't work on the equator because the gnomon would be flat and not cast a shadow. In this situation you would use an equatorial or vertical dial.If all you have is an horizontal dial you can use the trick of propping up the back with a wedge(at 35 degrees in this example) so that the gnomon points to the north celestial pole . You can also use this trick to adapt a dial that's made for a latitude that's different than yours.
what is the websites
so The Compass is a Lie? :
There are several 'norths'. The two that matter here, I think, are magnetic and geographic north.
then I would wait for the sun to be straight up and know it was noon.
The sun won't be straight up at noon unless you are on the equator and it's an equinox or if you're on a Tropic (of Cancer or Capricorn) and it's a corresponding solstice....or somewhere between the Tropics and it's whatever corresponding day that the sun is directly overhead at noon. If you aren't within the Tropics it'll never happen and even then, technically only for one day.
Lots of stuff missing here. For one thing, there needs to be to 'noons' due to the thickness of the gnome causing it to cast 2 shadows simultaneously. Also, the importance of the difference between magnetic and true north are sort of glossed over here. There are a few other things, as well. Depending on how accurate you want your sundial to be, you might look elsewhere.
... but at least one can learn the basic principals. That's all I was offering. You should post a video explaining what I missed. :)
The Mars Science Laboratory has a sundial on it
zizo and carl do not do this bc we did it sorry
The easiest to build is an equatorial.
Earth is flat !
Łukasz Cukrovy I saw many videos on such topics; yet in my job as a simple land surveyor, the earth is curving. despite NASA and other professional development of science, There is four corners of the earth! 3 can be seen while the 4th is at gravity point( middle of the earth).
dont be stupid the earth has been scientifically proven that it isnt flat
Yes it is.......flat as a cue ball.