Solar Corona (2009 July 26)

Comments and questions about the APOD on the main view screen.
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MARSHALL SILER
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Solar Corona (2009 July 26)

Post by MARSHALL SILER » Sun Jul 26, 2009 12:15 pm

Does today's APOD (26 Jul 09) of the sun clearly show a magnetic field?

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neufer
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Re: Solar Corona

Post by neufer » Sun Jul 26, 2009 12:23 pm

MARSHALL SILER wrote:Does today's APOD (26 Jul 09) of the sun clearly show a magnetic field?
Yes.
---------------------------------------------
The Big Corona (2009 July 26) http://apod.nasa.gov/apod/ap090726.html
http://en.wikipedia.org/wiki/Corona_(beer) wrote:
<<Corona (labeled Corona Extra) is a brand of pale lager owned and produced by Cerveceria Modelo in Mexico. It is the top-selling beer in Mexico and is one of the top selling beers worldwide. All Corona beer is brewed and bottled in one of 7 Modelo Breweries in Mexico. Outside of Mexico, Corona is often served with a wedge of citrus fruit, usually lime. Unlike many beers, Corona is bottled in a clear bottle, increasing the opportunity for spoilage. Exposure to sunlight or light from fluorescent bulbs such as those used in refrigerated display cases significantly damages the taste of beer, yielding a taste that is often described as "skunky". This is the result of the essential hop oils spoiling due to UV exposure. However, during distribution, Corona is not typically stored in direct sunlight.>>
---------------------------------------------
The Big Kahuna (1959 July 26)
http://en.wikipedia.org/wiki/Kahuna wrote:
<<Kahuna is a Hawaiian word, defined as a "Priest, sorcerer, magician, wizard, minister, expert in any profession." The use of the term in reference to surfing can be traced back to the 1959 film Gidget, in which "The Big Kahuna", played by Cliff Robertson, was the leader of a group of surfers. The term then became commonplace in Beach Party films of the 1960s such as Beach Blanket Bingo, where the "Big Kahuna" was the best surfer on the beach.
  • Moondoggie: Don't you find Kahuna to be a little on the lazy side?

    Gidget: Love makes room for fault.>>
---------------------------------------------
Art Neuendorffer

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Re: Solar Corona

Post by bystander » Sun Jul 26, 2009 12:39 pm

neufer wrote:
http://en.wikipedia.org/wiki/Corona_(beer) wrote: ...
Unlike many beers, Corona is bottled in a clear bottle, increasing the opportunity for spoilage. Exposure to sunlight or light from fluorescent bulbs such as those used in refrigerated display cases significantly damages the taste of beer, yielding a taste that is often described as "skunky". This is the result of the essential hop oils spoiling due to UV exposure.
...
That's probably why I don't like Corona. Hmmm, live and learn.

Man law: Don't fruit the beer.

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Re: Solar Corona

Post by apodman » Sun Jul 26, 2009 1:45 pm

neufer wrote:
http://en.wikipedia.org/wiki/Kahuna wrote:Kahuna is a Hawaiian word, defined as a "Priest, sorcerer, magician, wizard, minister, expert in any profession."
Cohen is a Hebrew word, defined as "Priest", indicating a family claiming descent from Aaron, brother of Moses and the first high priest, from the Hebrew kohen or kohein, meaning priest.

Some have tried, perhaps in jest, to link the etymology of Kahuna to that of Cohen. Time to call that anthropologist again.

---
bystander wrote:Man law: Don't fruit the beer.
Agreed. Putting lime in beer is an abomination and an offense to nature. Corona is also guilty of the ancient sin and offense to astronomy of putting the (lime wedge shaped) moon at an impossible angle in their television commercials (unless there's a warm sandy beach I don't know about in Antarctica).

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Re: Solar Corona

Post by neufer » Sun Jul 26, 2009 2:28 pm

apodman wrote:
http://en.wikipedia.org/wiki/Kahuna wrote:Kahuna is a Hawaiian word, defined as a "Priest, sorcerer, magician, wizard, minister, expert in any profession."
Cohen is a Hebrew word, defined as "Priest", indicating a family claiming descent from Aaron, brother of Moses and the first high priest, from the Hebrew kohen or kohein, meaning priest. Some have tried, perhaps in jest, to link the etymology of Kahuna to that of Cohen. Time to call that anthropologist again.
http://en.wikipedia.org/wiki/Chiang_Min_people wrote:
<<The "Ten Lost Tribes of Israel" refers to the ancient Tribes of Israel that disappeared from the Biblical account after the Kingdom of Israel was destroyed, enslaved and exiled by ancient Assyria... The Chiang Min people of northwest China claim to be descendents of Abraham. Tradition holds that their forefather had 12 descendents and in times of trouble, they call God in the name of "Yawei", the same as Yahweh. Idol worship is forbidden and anyone who offers a sacrifice to another god faces the death penalty. Some of them still look Semitic:

Image
[Note the Fractal costumes]

Chiang Min priests wear clean white clothes and perform the sacrifices in a state of purity, like the priests in ancient Israel (1 Samuel 15:27). Unmarried men may not be a priest, which was the same in ancient Israel (Leviticus 21:7, 13). Like the ancient altar of the Torah, which could not be made of cut stones (Exodus 20:25) the Chiang Min altars are built of earth which is molded into stones which are then laid one on top of the other without being cut of fashioned by any tool of metal. The main part of the Chiang Min service is performed at night, as is done in ancient Israeli tradition. After the 7th day or at the eve of the 40th day of the child's life, a white rooster is slaughtered in the child's honor and he is given a name.>>
apodman wrote:
bystander wrote:Man law: Don't fruit the beer.
Agreed. Putting lime in beer is an abomination and an offense to nature. Corona is also guilty of the ancient sin and offense to astronomy of putting the (lime wedge shaped) moon at an impossible angle in their television commercials (unless there's a warm sandy beach I don't know about in Antarctica).
http://en.wikipedia.org/wiki/Lime_(fruit) wrote:
<<Lime is a term referring to a number of different fruits which have their origin
in the Himalayan region of India [which was formally a beach near Antarctica].

In order to prevent scurvy during the 19th century, British sailors were issued a daily allowance of citrus such as lime, which led in time to the nickname "limey" for all Britons. Lime is also used occasionally to enhance vision by many Asian martial artists by squeezing a drop or two on the inside corner of the eye. This should not be done on a daily/routine basis.

Lime juice can be used to make your hair become lighter with sun exposure,
however it can make your skin darker with sunlight.
>>
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Re: Solar Corona (2009 July 26)

Post by Chris Peterson » Sun Jul 26, 2009 2:39 pm

MARSHALL SILER wrote:Does today's APOD (26 Jul 09) of the sun clearly show a magnetic field?
Yes. And no.

To be clear, the image captures nothing but light, and that's all it shows. But the structure in the corona is created partly by how the material interacts with the Sun's magnetic field, so what you see is indirectly revealing details about that field. It's kind of like sprinkling iron filings on paper over a magnet: you don't actually see the magnetic field, but that field's interaction with the iron lets you visualize its shape.
Chris

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Re: Solar Corona

Post by apodman » Sun Jul 26, 2009 2:42 pm

neufer wrote:Image
[Note the Fractal costumes]
How could I not have noticed that Mandelbrot was also a Chinese name?
neufer wrote:the Himalayan region of India ... was formally a beach near Antarctica
Is that "formerly", or is it a black tie (and ceremonial fractal costume) beach?

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A Question about 33 photos of the sun's corona on 7/26/09.

Post by John PS » Sun Jul 26, 2009 3:30 pm

Today's photo of the sun's corona was created from 33 photos. Were the photos all taken at the same exact time, each with different filters, etc, and is the image of the corona the way it appeared at one point in time or is the corona as it appeared over a span of time?

Thanks

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Re: Solar Corona

Post by neufer » Sun Jul 26, 2009 3:44 pm

apodman wrote:
neufer wrote:the Himalayan region of India ... was formally a beach near Antarctica
Is that "formerly", or is it a black tie (and ceremonial fractal costume) beach?
http://realitology.com/wp-content/uploa ... beach1.jpg
Last edited by neufer on Sun Jul 26, 2009 4:51 pm, edited 1 time in total.
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Re: A Question about 33 photos of the sun's corona on 7/26/0

Post by neufer » Sun Jul 26, 2009 3:56 pm

John PS wrote:Today's photo of the sun's corona was created from 33 photos. Were the photos all taken at the same exact time, each with different filters, etc, and is the image of the corona the way it appeared at one point in time or is the corona as it appeared over a span of time?
I'm not sure that filters were used so much as it was a process of digitally mixing
& matching over exposed and under exposed time integrated digital "photos" :

http://asterisk.apod.com/vie ... 37#p108531
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Re: A Question about 33 photos of the sun's corona on 7/26/0

Post by Chris Peterson » Sun Jul 26, 2009 4:12 pm

John PS wrote:Today's photo of the sun's corona was created from 33 photos. Were the photos all taken at the same exact time, each with different filters, etc, and is the image of the corona the way it appeared at one point in time or is the corona as it appeared over a span of time?
Almost certainly the multiple images were taken over a period of time. I've shot total solar eclipse images that way, and it works fine as long as some care is taken to keep the total exposure fairly short. The coronal structure doesn't change over a few minutes, but you can have problems with the lighting near the beginning and end of totality. This particular eclipse was unusually long, which allowed for more latitude in taking corona images from multiple shots.

You don't typically use filters, but simply take images at different exposure times or apertures, so you selectively expose for different regions of brightness. That's actually an increasingly common technique in normal terrestrial photography- combining two or three images taken at different exposures to provide detail in shadows and highlights. At least one camera can do this internally and automatically.
Chris

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Re: Solar Corona (2009 July 26)

Post by Pete » Sun Jul 26, 2009 5:16 pm

Chris Peterson wrote:[...] combining two or three images taken at different exposures to provide detail in shadows and highlights. At least one camera can do this internally and automatically.
High dynamic range imaging. All too often I think "nice graphics" and then realize I'm looking at an HDR image and not a Crysis screenshot.

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Re: Solar Corona (2009 July 26)

Post by geckzilla » Mon Jul 27, 2009 4:53 pm

HDR photography seems to also mean you are supposed to super-saturate your photos and also be sure to include those weird fuzzy light and dark gradients when coming towards an edge to increase clarity but take it so far that it looks unnatural and kinda messed up. Thankfully, the APOD pic doesn't do either. :)
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Re: Solar Corona (2009 July 26)

Post by Chris Peterson » Mon Jul 27, 2009 5:03 pm

geckzilla wrote:HDR photography seems to also mean you are supposed to super-saturate your photos and also be sure to include those weird fuzzy light and dark gradients when coming towards an edge to increase clarity but take it so far that it looks unnatural and kinda messed up. Thankfully, the APOD pic doesn't do either. :)
HDR is just that: high dynamic range. Astroimagers do it all the time (nearly every image is high dynamic range). The catch is that our display devices (and even our eyes) don't have the same range as our data, so we need to come up with effective ways of compressing the range. Like anything else, you can do it well, or you can do it badly.
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Re: Solar Corona (2009 July 26)

Post by geckzilla » Mon Jul 27, 2009 11:43 pm

Super saturating every colored bit of an image is actually the opposite of dynamic range, however. That's why I dislike it. If one's photo is to have high dynamic range, it ought to be not only in tonal value but also in hue as well. To pump the colors up too far is similar to doing a cheap contrast adjustment and blowing out your shadows and highlights. Is that more understandable? And to further clarify I was speaking of terrestrial photography rather than astroimagery. I don't mind the fakeness (for lack of better word, fake is probably wrong) of astroimagery since if it were closer to how it looks in reality it would probably be rather dark.
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Re: Solar Corona (2009 July 26)

Post by Zbig912 » Tue Jul 28, 2009 6:12 am

"WYSIWYG=or photography without borders"
The magnificent picture of the Corona of the Sun shown on July 26, 2009 prompted me to register to this forum. For quite a few years I observe how the software technologies lead us to better and better picture, displaying whatever we want. On the other hand we have those beautiful moments with a good apochromat or with big DOB in a dark place, e.g. in a desert where we are left with our thoughts and keep some intimacy between our mind and the Universe. And that is what the amateur astronomy is about! I am not an expert in photography but whenever I see some ones astro-picture or I photograph myself I always ask myself a question if the picture is able to resemble the atmosphere of that day including my feelings and/or other persons feelings.
Now in many cases we can look at these beautiful pictures like the one of Solar Corona by Koen van Gorp shown on July 26, 2009 and think perhaps it is beautiful but not true.
On July 22nd 2009 near Xiantao and we were among very few that day in China to observe the eclipse on clear sky. Thus in my opinion those beautiful pictures using either 12 stacked pictures (Photo Gallery of S&T) or the picture by Koen van Gorp simply go too far with processing technique. For many reasons professional astronomers do with their pictures even more advanced changes, but they do it with a research purpose to highlight particular, analyzed element.
I took also some pictures of perhaps mediocre quality but they are far closer to the feelings of that day & that location. See link to my whole short report here
http://www.z.zembaty.po.opole.pl/Eclips ... urney.html
I still keep in mind the Corona like on the 5th picture shown in the link above.
http://www.z.zembaty.po.opole.pl/Eclips ... ml/z04.jpg

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Re: Solar Corona (2009 July 26)

Post by fugfar » Tue Jul 28, 2009 10:06 am

thats AWESOME!!!

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Re: Solar Corona (2009 July 26)

Post by Chris Peterson » Tue Jul 28, 2009 9:37 pm

Zbig912 wrote:Now in many cases we can look at these beautiful pictures like the one of Solar Corona by Koen van Gorp shown on July 26, 2009 and think perhaps it is beautiful but not true.
What I would say is that the image is not only beautiful, but more true than many other images because it actually shows more than the eye can see. If the image claimed to be an accurate representation of what you see at a total eclipse, I'd disagree. But it is specially processed to bring out extreme detail that normally isn't visible to the eye.
On July 22nd 2009 near Xiantao and we were among very few that day in China to observe the eclipse on clear sky. Thus in my opinion those beautiful pictures using either 12 stacked pictures (Photo Gallery of S&T) or the picture by Koen van Gorp simply go too far with processing technique. For many reasons professional astronomers do with their pictures even more advanced changes, but they do it with a research purpose to highlight particular, analyzed element.
We need to consider the intent of the image and the imager before deciding if something goes too far. Many amateurs are no less interested than professionals in capturing the maximum amount of data, and then presenting it visually in an effective way. I think the sort of composite images you describe fall into that category.
I took also some pictures of perhaps mediocre quality but they are far closer to the feelings of that day & that location.
The images are very nice, and I agree that the fifth one down comes close to catching the visual appearance of the corona, although the eye does have more dynamic range and sees a little more detail. But that type of image does match visual reality fairly well, and is beautiful in its own way. I have a somewhat similar image from a different eclipse here. Although I'm pleased with the images I got, I wouldn't mind having a richer set of digital images to do some interesting processing.
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Re: Solar Corona (2009 July 26)

Post by apodman » Tue Jul 28, 2009 11:29 pm

Taking photographic processing "too far" is when you start enhancing noise, calling it information, and showing features that aren't there. The solar corona picture in APOD 2009 July 26 is certainly not in that category.

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Re: Solar Corona (2009 July 26)

Post by Zbig912 » Wed Jul 29, 2009 2:09 am

apodman wrote:Taking photographic processing "too far" is when you start enhancing noise, calling it information, and showing features that aren't there. The solar corona picture in APOD 2009 July 26 is certainly not in that category.
There is this very delicate difference between what "was there" and "what could be seen". I would only like to concentrate with the astro-pictures on reflecting the time, the place and the observer which ulitimately is human eye.

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Re: Solar Corona (2009 July 26)

Post by Chris Peterson » Wed Jul 29, 2009 2:23 am

Zbig912 wrote:I would only like to concentrate with the astro-pictures on reflecting the time, the place and the observer which ulitimately is human eye.
That's certainly a perfectly reasonable goal for an imager. For myself, I find the view through a telescope generally boring. The eye is extremely limited when viewing astronomical targets; I love seeing the vast amount of detail that an image can capture that the eye will never see.
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Re: Solar Corona (2009 July 26)

Post by Zbig912 » Wed Jul 29, 2009 2:27 am

Chris Peterson wrote:
Zbig912 wrote:Now in many cases we can look at these beautiful pictures like the one of Solar Corona by Koen van Gorp shown on July 26, 2009 and think perhaps it is beautiful but not true.
What I would say is that the image is not only beautiful, but more true than many other images because it actually shows more than the eye can see. If the image claimed to be an accurate representation of what you see at a total eclipse, I'd disagree. But it is specially processed to bring out extreme detail that normally isn't visible to the eye.
On July 22nd 2009 near Xiantao and we were among very few that day in China to observe the eclipse on clear sky. Thus in my opinion those beautiful pictures using either 12 stacked pictures (Photo Gallery of S&T) or the picture by Koen van Gorp simply go too far with processing technique. For many reasons professional astronomers do with their pictures even more advanced changes, but they do it with a research purpose to highlight particular, analyzed element.
We need to consider the intent of the image and the imager before deciding if something goes too far. Many amateurs are no less interested than professionals in capturing the maximum amount of data, and then presenting it visually in an effective way. I think the sort of composite images you describe fall into that category.
I took also some pictures of perhaps mediocre quality but they are far closer to the feelings of that day & that location.
The images are very nice, and I agree that the fifth one down comes close to catching the visual appearance of the corona, although the eye does have more dynamic range and sees a little more detail. But that type of image does match visual reality fairly well, and is beautiful in its own way. I have a somewhat similar image from a different eclipse here. Although I'm pleased with the images I got, I wouldn't mind having a richer set of digital images to do some interesting processing.
I agree about these two types of images. For example in artistic photography you can always experiment to show your impression rather than what was seen. But for artistic photography impression is the right target. However for amateur astronomy the result is that people more and more time spend at the computer than actually observing. This becomes more and more software race. Soon people will stop taking pictures, but will download RAWs from professionals and concentrate on enhancing them.
I like your picture of the eclipse in India. They illustrate exactly what I mean - the time, the location, the feelings.

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Re: Solar Corona (2009 July 26)

Post by Zbig912 » Thu Jul 30, 2009 8:52 am

Chris Peterson wrote: For myself, I find the view through a telescope generally boring. The eye is extremely limited when viewing astronomical targets;
Apart from personal impressions (which are quite subejctive) there are however evident cases when human eye see much better. These are, for example, globular clusters. Compare Omega Centauri (or at least M13) by an 8" Newton in good conditions to see how even good photography can not properly reflect these resolved blue pin-point giants over the fuzzy background. In addition when observing Omega Centauri and slightly moving your field of view you may almost capture the 3D effect.
Anyway I do not insist observing is better than photographing - I just insist these are two different realms.

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