SunPosition calculations online

[sunposition]

You guys should find this useful...

There is an online version of SunPosition software for calculating sunrise, sunset, shadow factor and plots the suns position throughout the day at 15 minute intervals. Options for making calculations using true or magnetic north, also compensates for GMT offset and DST.

SunPosition http://www.sunposition.net/

Members get access to over 48,400 worldwide locations at the time of this post, non members have access to 8,000 locations. Members can print out a graph and sun path professionally formatted to an A4 page and add locations to their own favourites menu along with the capabilities of creating their own personal locations, all this starts at US$18 per year for a single user license (15 euros).

No need to pay for upgrades or different versions for different computers, users can log in from any computer anywhere in the world as long as it has an internet connection and a browser. Locations are added continually so the database keeps growing, need a location thats not listed? just let the people know at SunPosition know and it will be added for you if you don't want to add it yourself.

A example SunPosition printer friendly formatted page that all members get access to can be seen by non members by selecting the location: Europe / Spain / MADRID (M) then after making the calculation for this location press the 'Printer friendly' button.

This really is a great online application that was created for Photographers, DoP's, Directors, Engineers etc. it is probably the most accurate sun positioning software you will find anywhere.

[Ole Tjugen]

Worked fine for Madrid, but hangs when I try calculating for Kirkenes, Norway. Maybe it has a problem with midnight sun? And why isn't the second largest city in Norway in the list, while lots of insignificant little places close to the capital are?

I think I'll stick with the free astronomical services, thank you.

[sunposition]

Worked fine for Madrid, but hangs when I try calculating for Kirkenes, Norway.

Strange that no-one else has reported any hangs! maybe you have a problem with your browser?

The graph for that location shows the result but it is offset towards the bottom of the graph because of the suns location in that area. Mind you, looking at the calculation the suns position isn't really going to help much with your photography at the moment at that location! :)


And why isn't the second largest city in Norway in the list, while lots of insignificant little places close to the capital are!

Maybe you haven't read this bit... members get access to over 48,000 locations while non members get access to just under 8,000.


I think I'll stick with the free astronomical services, thank you.

No worries, everyone is free to use whatever they need or like to use. Many photographers ' and others' find SunPosition very useful for their needs, if you don't then that is up to you. :)

Cheers

[Leonard Evens]

I agree with Ole. I will stick with Jeff Conrad's free calculator at
www.largeformatphotography.info/sunmooncalc/
It doesn't provide a graph nor does it correct azimuth for magnetic north. But I don't need the graph, nor do I need to use a compass. It does allow me to choose Chicago, Illinois without having to pay for it. If I want the answer more accurately for my location just north of Chicago, I can specify my latitude and longitude.

By the way, I'm sure there is a free calculator out there somewhere which also produces a graph.

I doubt strongly that typical frequenters of this website will be convinced of the value of this tool.

[Colin Graham]

Hey, you have Joyce WA on the list! Very cool. Not that the suns breaks through much this time of year... Stilll, could come in very handy, many thanks. I put it next the tide tables in my bookmarks.

[Ole Tjugen]

The graph for that location shows the result but it is offset towards the bottom of the graph because of the suns location in that area. Mind you, looking at the calculation the suns position isn't really going to help much with your photography at the moment at that location! :)

First of all, note the five month offset between my post and your reply. There is plenty of sun in Kirkenes in July - thery have midnight sun up there, so it can be quite useful knowing where the sun will be at ALL times of the day.

And while the sun doesn't come up at all this time of the year, there is still enough light for photography.



Maybe you haven't read this bit... members get access to over 48,000 locations while non members get access to just under 8,000.

I did read that part - I was just wondering about a selection process which includes some places so small I've never heard of them among the 8,000?

Compare the coordinates for Oslo, Grorud and Nydalen, Ljan, and Røa - they are close enough that any differences are insignificant, especially considering the geographic spread of the rest of Norway! "Roa" is a different place, "Røa" should be spelled "Roea" if you can't use the correct letters.

"Valand" is placed in a part of Stavanger city, close to Hillevåg. I have no idea where you found that name? I assume "Lambergsaeter" is supposed to be Lambertseter, but the position given is Skullerud? "Bratan" I have no idea of, but the location is on the outskirts of Drammen. "Folkvang" also draws a blank, it seems to be in a forest near Porsgrunn.

So it still doesn't inspire me to spend money, even if I didn't have any problems with Kirkenes this time - nor when doing the calculations for July 20th. :)

[Eirik Berger]

Crap, so it is actually true that the sun is still 11 degress under the horizon at noon. Not good lighting conditions for photography :(

[sunposition]

I did read that part - I was just wondering about a selection process which includes some places so small I've never heard of them among the 8,000?

There are places I have never heard of also, the names are from the sites mentioned below or entered by other users who film, shoot or work at those locations.


Compare the coordinates for Oslo, Grorud and Nydalen, Ljan, and Røa - they are close enough that any differences are insignificant, especially considering the geographic spread of the rest of Norway! "Roa" is a different place, "Røa" should be spelled "Roea" if you can't use the correct letters.

"Valand" is placed in a part of Stavanger city, close to Hillevåg. I have no idea where you found that name? I assume "Lambergsaeter" is supposed to be Lambertseter, but the position given is Skullerud? "Bratan" I have no idea of, but the location is on the outskirts of Drammen. "Folkvang" also draws a blank, it seems to be in a forest near Porsgrunn.

The base database of 47,000 was started from files of over 6 million locations, these where filtered through scripts a few hundred times to try and remove non populated places and most non desired places, the names are all part of the database information supplied by:
http://www.nga.mil/portal/site/nga01/
and
http://geonames.usgs.gov/
so that is where they come from. It is a fairly major process of filtering 6 million down to 47,000 and still keeping 90% of the locations as populated places! the other 1,000 odd where added by hand or by members as mentioned above.


So it still doesn't inspire me to spend money, even if I didn't have any problems with Kirkenes this time - nor when doing the calculations for July 20th

Ole, as I mention before, everyone is free to use whatever they need or like to use. Many photographers ' and others' find SunPosition very useful for their needs and that is why it is mentioned here, if you don't then that is up to you. :)

Leonard [Evens], I think it is not good to look at things from inside a box, just because some people may find they may not need something for their needs doesn't mean to say that others don't or won't have wider needs :)

Enjoy your day. :)

[Leonard Evens]

I stick with what I said. I don't think many LF photographers would find it worthwhile paying for this software when there are other free alternatives, such as Jeff Conrad's calculator, available at lfphoto.info, which are as well suited or better for their needs.

I also still don't see why you left Chicago, Illinois out of the list of sites available for free. After all, it is hardly a small uninteresting city where few people live. I bet many other important locations were also omitted.

[cowanw]

Toronto, Canada
Regards
Bill

[sunposition]

I stick with what I said. I don't think many LF photographers would find it worthwhile paying for this software when there are other free alternatives, such as Jeff Conrad's calculator, available at lfphoto.info, which are as well suited or better for their needs.

You mean it's hosted on: http://www.largeformatphotography.info
OK, I understand now. :)


I also still don't see why you left Chicago, Illinois out of the list of sites available for free. After all, it is hardly a small uninteresting city where few people live. I bet many other important locations were also omitted.

I am sorry you can't understand why most of the important locations are omitted from the non members area!

I could go into a long answer here but to be honest, I will leave it up the users preference... as I have said a couple of times now. :)

[Joseph O'Neil]

Not to insult anybody, but this whole thread has me puzzled. This kind of information has been freely available on various software platforms in many astronomical/planetarium programs for a while. For example:
http://www.midnightkite.com/software.html
http://freeware.intrastar.net/planetarium.htm
http://www.r-clarke.org.uk/astrosoft1.htm

..and there are more. The software is not all that hard to write - I did it once myself many moons ago when I used to program a bit in turbo pascal. Point is, determining basic sun and moon positions for any given time and lat & long. is the basic staple of any planetarium program, and I've had software that can do this since the days of the Commodore 64. Today, to get you lat & long, all you have to do is look it up on Google maps, punch in the location & save it in your planetarium program, and away you go.

joe

[Winger]

http://aa.usno.navy.mil/data/docs/AltAz.php

[Leonard Evens]

Joseph,

I was trying to make just your point, and in addition there is a link on this very web site to such a calculator.

On a vaguely related matter, do you have some good references which explain the mathematics behind the Equation of Time and related matters? I've just read "Marking Time" by Duncan Steel, which I found fascinating. It has appendices which explain it pretty well in words, but, as a mathematician, I am curious about the analytic details.

[BrianShaw]

Not to insult anybody, but this whole thread has me puzzled.

I've been puzzled since the first reply. What is all the emotion about? I have no need for such data, and found it real easy to think "thanks, but no thanks". It is all very puzzling to me.

[Joseph O'Neil]

On a vaguely related matter, do you have some good references which explain the mathematics behind the Equation of Time and related matters? I've just read "Marking Time" by Duncan Steel, which I found fascinating. It has appendices which explain it pretty well in words, but, as a mathematician, I am curious about the analytic details.

Hi;
Not exactly what you are looking for, but try and find a book called "Astronomical Algorithims" by - I think from memory - Jean Meesus. It was written about 15 years ago, and is a large collection of algorithims for anyone wanting to write their own software under any language.

It does not deal specifically with time, but I think you might enjoy it as it relates to time, movement of celestial bodies, different measurements of time, etc.
good luck
joe

[Leonard Evens]

Hi;
Not exactly what you are looking for, but try and find a book called "Astronomical Algorithims" by - I think from memory - Jean Meesus. It was written about 15 years ago, and is a large collection of algorithims for anyone wanting to write their own software under any language.

It does not deal specifically with time, but I think you might enjoy it as it relates to time, movement of celestial bodies, different measurements of time, etc.
good luck
joe

Thanks for the reference. It turns out to be Jean Meeus, and I found a copy for about $16 at Powell Books.

[sunposition]

Just to update this thread:

The SunPosition domain has been changed to: http://sunposition.info

Because of the popularity of the SunPosition widget we have had to change our domain name, this is because of an excessive number of requests to the domain from our widget which in turn was creating an excessive load on the server. Changing the domain was the only solution available to us to combat this problem.

The SunPosition service is now available at the above domain.

For SunPosition widget users: At the time of posting the SunPosition widget will be disabled as the URL's used for calculation data pickup will have been shut down, we are currently working on an updated version of the widget that will be modified to help the server cope with such an excessive number of requests.

Regards
sunposition