A photographer emailed me yesterday to say that this week the sun will set behind a particular landmark in San Francisco, but he didn't (won't) say how he figured it out.

How does one do that, and where can I go (online?) to learn that? For example, I'd like to know when the moon will rise over the peak of Mt. Diablo in California and where I'd have to be to photograph it. Also, when does the sun set between the two towers of the Golden Gate Bridge in San Francisco, and where I'd have to be to photograph it. You get the idea.

Anyone know how to do the calculations and where I can go to learn it?

Thanks very much!!

Gary
web.mac.com/misterellis

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

All you need is a map and compass and some careful analysis.

Second link from google:

http://www.largeformatphotography.info/sunmooncalc/

or download google earth and you can do the same graphically.

And please don't cross-post the same message to multiple forums.

Well that is all well and good information. but I know another way, that lets you see what the effect will be on objects !!

3D Studio Max will give you the exact light conditions from any city At any time of day of the year or month !!

if is perhaps the most popular 3D program out there, you can download a 30 day free trial from Autodesk dot com

80% of todays' games are made in this 3D program, there is nothing this program cannot do or create !!

In photography you can only create images of that which you can 'see'.

In 3D studio Max you can create anything you can possibly think of with perfect photo realistic results that can also be animated !!

this is the most exciting world I have ever ventured into, complete with all the laws of physics and nature !!

In Google Earth you can see exactly how the procession of the equinox and the timing works by enabling View > Sun. pretty easy.




Majik.... 3DS Max is cool, but you sound a bit like a commercial . Also, you can do some pretty cool stuff in it for photography as well, Check out "View Independent Photography." It is still the exact scene, but goes a step beyond photo-realism to just plain virtual-realism, IMO.

So sorry for 'sounding' like a commercial !! that was not my intent, rather just to provide another method for determining sunlight in any city at any time of day month or year.

I think that the Cannon / Nikon '"commercials" far outweigh my mention of 3D Studio Max !!

very few people are aware of this incredible program !!

Search this site for Michael's review of Planetarium, a small but very clever program for Palm hand-held computers. This program tracks sunrise & sunset, moonrise/moonset and lunar phase, for any place in the world. All you have to do is enter lat/long. data, and choose your time & date. I find it invaluable. Either home or away, I always know when there will be a full moon, a photogenic crescent moon at twilight, and the precise time and direction of sunrise. And it fits in your pocket.

There are also several programs for the iPhone that will give ephemeris data for the Sun and the Moon. Astromo is one in particular that I use.

However, I wasn't aware of the 'View->Sun' feature in Google Earth - that's really excellent. I just played with it and for shooting in north-south aligned valleys it would appear to be a real help in figuring out just what will be illuminated at what time of year. Great stuff.

For example:


The last time I was there it was a little later, so Carrauntoohil (the big mountain at left) was mostly in shade.



Peter

whoa !! I gotta admit, that is pretty slick !!

Lots of useful readymade solutions listed here; I find Google Earth pretty useful for trip planning.

I'm curious if anybody of any sources of information on how to calculate this information (sample source code would be great too). I've been wanting to write an app for my smart phone to do this. There are a few out there now (Ephemeris comes to mind), but they have limited location databases and entering long/lat can be a pain. My plan is to write my own app to do the calculations, using phone's GPS to get the location coordinates.

In case you don't come across any better sources (no pun intended), the relatively old books Practical Astronomy with your Calculator and Astronomy with your Personal Computer, both by Peter Duffett-Smith, are still available. They describe how to do the calculations.

Use http://www.timeanddate.com/
for sunrise/sunset and moon rise/set times and azimuth. Prints tables for one month for any town globally.

The same for WinCE-based hand-helds : Ephemeris 1.0 by Jonathan Sachs( (of DL&C, the maker of Picture Window Pro).
Found via the same!

There's a free moon position calculator at www.findthemoon.com which allows you to put a target in the sky in a google earth interface and ask 'when will the moon be in that target'. It returns a list of dates and times with azimuth, elevation and brightness. You can line up the a landmark with the target and use the results to plan and precompose your shot.

I found this freeware, The Photographer's Ephemeris. It uses google map/earth. Very nice, provides
ephemeris information from anyway, directional lines of sun/moon rises/sets of different dates. One
can save several locations.

http://stephentrainor.com/tools

Enjoy.