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Multiple Exposures Of The Sun
Stormbringer_X1 writes "This image holds many first. Called an analemma (a figure 8 loop), it is a multiple exposure of the sun, where one observes the sun at the same time of day, over the period of a year. The patience and dedication to pull this off are emphasized by the fact that there are so few in existence (7 total including the first in 1979). It is the first analemma imaged in a single calendar year, the first on the southern meridian, and the first in Greece. The author has other images from 2002 that will be available soon. So stay tuned. Here is an image from NASA archives"
...what's so hard about it?
Bah, looks like 3 minute job with a white paintbrush in the GIMP. :-)
Seriously, though, at least some of this *has* to be a photo-manipulated composite, or else they never would have gotten that cloud in the background.
May we never see th
"Single piece of film" is apparently one of the requirements. You could do it with a digital camera, but then it wouldn't count...
Pathman, Free (as in GPL) 3D Pac Man
How many images does he have to take to qualify?
why is it so difficult? If you have a home in an area not affected by earthquakes then surely you can't just leave a tripod set up and do an exposure every week or so
If this is a single film photo, then there are a couple of things disturbingly wrong:
1. The shadow on the parthenon is no in line with the suns
2. the suns look like frightingly stupid white circles
3. the cloud in the lower left corner can only be on the picture if that particular cloud is there every time the film is exposed
--- Sigmentation Fault - Comments Dumped
There is nothing wrong with the image.
41 pictures were taken with a solar filter on - after which the negative was unexposed except for the 41 "dots" that are the sun.
The solar filter is then taken off. The photographer waits until the frame looks good and the negative is then exposed one more time to "add" the foreground. The cloud and the Parthenon are only exposed once.
Judging from the shadows and the fact that the suns are due south, the foreground shot was taken in the morning (lit from left, which is east).
- Tony
My guess is that the exposure of the parthenon was taken either before or after the solar ones (most likely after) when the sun was not in the camera's FOV (i.e. at another time of day). This is the reason that the shadows on the partenon look wrong.
Since the sun is so bright, the rest of the film is still relatively unexposed, and the picture of the parthenon (inc. cloud) can be taken more or less as if it were a regular photograph.
Pathman, Free (as in GPL) 3D Pac Man
We go around the sun pretty smoothly, right? Shouldn't the path that the sun traces be a smooth one? On the image with the Parthenon, there is some time issues certainly, but the wiggle off of a "perfect" figure 8 shows that the camera wasn't always replaced exactly the same.
Nice try, nice image, but not as good as the second image pointed to in the article. That's why there are so few of these images around.
There are definitely more than just seven analemma exposures in existence. There was an issue of Sky & Telescope with six by amateur astronomers alone.
to do this with the Gimp - you people need to work on your photomanipulation skillz, werd!
It took him a year to do and required a lot of engineering including:
It is a facinating project and there have never been that many of these taken. The building in the picture is Bell Labs by the way.
The difference between Canada and the USA is that in Canada healthcare is a right and gun ownership is a privilege.
For something like this, wouldn't you want to use true local time instead of the time in the given timezone? Remember that time zones with the absence of daylight savings time are set up so that the sun is in the highest point in the sky at noon somewhere roughly in the middle of the time zone. Before time zones were created, each town set their clocks so that noon was true noon.
So the first thing to do in something like this is use GPS to determine your longituted and thereby compute the exact +/- UTC for your location.
If you've got a year's worth of webcam files with a view in the right direction just pull out one a month from the same time of day and composite them.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
How about using ISO 25 speed film in a camera with an EXTREMELY tiny aperture so that the whole exposure takes 1 year?? How about using a field camera maybe 6x7" kodak pan film?
The result will be the sun painting the sky strip by strip. Now that should be a first.. with the trees superimposed throughout the year.
Come to think of it, we can aim the camera at a mall or busy street area. With the blurs, you could see where people stand most and what color clothes they wear. You can definitely make out the dots where homeless people sit. Sounds like a feasable project... hmmm..
"Give orange me give eat orange me eat orange give me eat orange give me you." -Nim Chimpsky
In a chemistry lab at NRL, someone marked the position of a shadow at different times of the year on one hallway wall. Similar shape of course.
Here are some links if you're interested in more:
Qualitative and mathematical description of why the effect occurs.
Gallery of analemma images, description of construction and implementation of making one.
By the way, if you saw Cast Away, that was an analemma that Hanks' character used to keep track of the time he was stuck on the island. Hollywood took some liberty with the concept though, because it would have been impossible without an accurate timepiece of some kind.
So what about the Moon?. Does it cause any such stuff?.
Oops, my ignorance is out!