APOD: Total Totality (2024 Apr 12)

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APOD: Total Totality (2024 Apr 12)

Post by APOD Robot » Fri Apr 12, 2024 4:07 am

Image Total Totality

Explanation: Baily's beads often appear at the boundaries of the total phase of an eclipse of the Sun. Pearls of sunlight still beaming through gaps in the rugged terrain along the lunar limb silhouette, their appearance is recorded in this dramatic timelapse composite. The series of images follows the Moon's edge from beginning through the end of totality during April 8's solar eclipse from Durango, Mexico. They also capture pinkish prominences of plasma arcing high above the edge of the active Sun. One of the first places in North America visited by the Moon's shadow on April 8, totality in Durango lasted about 3 minutes and 46 seconds.

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Re: APOD: Total Totality (2024 Apr 12)

Post by florid_snow » Fri Apr 12, 2024 4:22 am

I saw this eclipse and the bright pink prominences were stunning, and it got me reading about H alpha emission. And after some reading, I feel betrayed by every "H alpha" filtered photo of the sun I have seen. Because the prominences appeared obviously PINK to human eyes, doesn't that mean that H alpha filtered images should be colored for "accurate human eye view" as either bright pink if we're being chemically accurate for all the emission lines of H or at least deep red for just the particular filter for H alpha emission?

And yet NASA images and astrophotographers tend to filter everything as an orange-ish color. It is like they can't trust the public to accept anything but a camp fire type color for the sun. But the true color of Hydrogen doing it's emission is obviously pink, as we all saw with our own eyes. Some photographers have to be brave enough to color their images with a semi-accurate pink color, right?

Edit: some examples:

Fake color:
Image

Realistic color:
Image

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Re: APOD: Total Totality (2024 Apr 12)

Post by Chris Peterson » Fri Apr 12, 2024 5:09 am

florid_snow wrote: Fri Apr 12, 2024 4:22 am I saw this eclipse and the bright pink prominences were stunning, and it got me reading about H alpha emission. And after some reading, I feel betrayed by every "H alpha" filtered photo of the sun I have seen. Because the prominences appeared obviously PINK to human eyes, doesn't that mean that H alpha filtered images should be colored for "accurate human eye view" as either bright pink if we're being chemically accurate for all the emission lines of H or at least deep red for just the particular filter for H alpha emission?

And yet NASA images and astrophotographers tend to filter everything as an orange-ish color. It is like they can't trust the public to accept anything but a camp fire type color for the sun. But the true color of Hydrogen doing it's emission is obviously pink, as we all saw with our own eyes. Some photographers have to be brave enough to color their images with a semi-accurate pink color, right?

Edit: some examples:

Fake color:
Image

Realistic color:
Image
Color is a physiological property, not a physical one. With a narrow wavelength, the hue is fixed but the color changes with intensity. The apparent color of H-alpha is determined by its intensity, as well as by any other colors mixed in with it. In the case of the eclipse, that means white light, which desaturates the deep red hue of H-alpha. If you view the Sun through an H-alpha filter, you will not see pink. You will see deep ruby red. Any image of an H-alpha source that is uncontaminated with other light should be processed to look red in its midtones, scaling towards warm white as it gets brighter and black as it gets darker.

The image you labeled "fake" is close to what the Sun looks like through my narrow band solar telescope. I've never seen anything like the one you label "realistic".

Indeed, to my eyes, the prominences in this eclipse were red. Not pink. Very similar to the color in today's APOD.
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Re: APOD: Total Totality (2024 Apr 12)

Post by Ann » Fri Apr 12, 2024 6:04 am

florid_snow wrote: Fri Apr 12, 2024 4:22 am I saw this eclipse and the bright pink prominences were stunning, and it got me reading about H alpha emission. And after some reading, I feel betrayed by every "H alpha" filtered photo of the sun I have seen. Because the prominences appeared obviously PINK to human eyes, doesn't that mean that H alpha filtered images should be colored for "accurate human eye view" as either bright pink if we're being chemically accurate for all the emission lines of H or at least deep red for just the particular filter for H alpha emission?

And yet NASA images and astrophotographers tend to filter everything as an orange-ish color. It is like they can't trust the public to accept anything but a camp fire type color for the sun. But the true color of Hydrogen doing it's emission is obviously pink, as we all saw with our own eyes. Some photographers have to be brave enough to color their images with a semi-accurate pink color, right?
Hi, florid_snow, I'm glad to see that there is someone else out there who deeply cares about color! :D

There are a couple of factors that decide how we see color. First, there is the wavelength of the color we see, which, in the case of hydrogen alpha, is 656 nm, which corresponds to this color, ███. Second, there is the question of what other wavelengths are mixed in, apart from the dominant one. Hydrogen alpha light is often mixed with some hydrogen beta too, which is this color, ███. There may be a small amount of hydrogen gamma too, which is this color, ███. Together these wavelengths create a color reminiscent of this, ███, or perhaps this, ███.

Careful RGB images will often show emission nebulas like this:


Emission nebulas are typically ionized by hot blue stars, and the color of the nebula may be influenced by the blue and purple light emitted by these stars.

But there is another factor that influences how we see color, and that is how our own eyes adapt to the color of the ambient light and judge color according to that information. I'm going to guess that you are old enough to remember incandescent light bulbs very well. The light they give off is really very yellow, maybe this color, ███, or this, ███.

Incandescent light bulbs give off very, very little blue light. Yet we have no (big) problems seeing the blue color of blue objects in a room illuminated by incandescent light. That is because our eyes and brains can see that blue objects in this yellow-suffused room are "comparatively blue" in relation to other objects in the same room.

In other words, our color vision is not absolute. I noticed that myself when I spent a few winters judging the color of the brightest stars in the sky, using a 40-inch telescope. I vividly remember seeing Arcturus as a brilliant shade of lemon yellow, but that was only on one occasion. At other times it looked pale peach. And sometimes I could see marvelous blue color in the stars of the Pleiades, but sometimes they looked barely blue-white.

I'm convinced that not everyone sees color in the same way. You say that you saw the prominences surrounding the limb of the Sun as pink during the eclipse. Well, Chris Peterson insists that he saw them as red. And wilddouglascounty insists that he saw a prominence as yellow-orange.

We see and interpret colors differently, but there is a physical reality behind it all that triggers our color vision. I'm interested in that "reality".


Consider the brightly colored background behind the iconic Horsehead Nebula:


As you can see, the color balance of these two images is very different. The background behind the Horsehead Nebula is very red, almost magenta-red, in Trevor Jones' image, but it is orange in David Ellison's image. In my opinion, Trevor Jones is right the abut the colors of this region in Orion, and David Ellison is, well, being artistic. The light behind the Horsehead Nebula, in case you're wondering, is very predominantly hydrogen alpha.

I once read in Sky & Telescope that the best way to observe the Horsehead Nebula was to view it through a hydrogen beta filter. That way, the Horsehead would look like a black shape against a dark gray background. Why not view the Horsehead through a hydrogen alpha filter? It's because our eyes are not at all sensitive to large patches of very faint hydrogen alpha, and both the Horsehead and the nebula background would look all black to us.

My point here is that the red background of the Horsehead Nebula does contain hydrogen beta light, because if it didn't, it would be useless to view it through a hydrogen beta filter. I conclude, therefore, that hydrogen alpha light almost always contains some hydrogen beta, too. And the presence of hydrogen beta will shift the hue of hydrogen emission away from a pure of red into a softer more complex hue.

You saw it as pink. That's absolutely correct, in my opinion. Chris Peterson saw it as intensely red. I can't fault him. And wilddouglascounty saw it as yellow-orange. I find that color surprising, but who am I to say that that is not what he saw?

Ann

Edit: As for the color of the Sun, it is a fact that it is often shown like this in NASA images:


So, confession. I hate it when the Sun is shown as deeply orange by NASA. In my opinion, this helps create the impression among the general public that the Sun is "really" orange, and we just can't see its true color because it's too bright.

All right. These "orange Sun images" typically show the Sun in invisible ultraviolet light. I have argued about it here at Starship Asterisk, and I've been told that it is very good to show the ultraviolet Sun as orange, and it would have been "wrong", or at least unwise, to show it as, say, blue. Or pink.

I keep insisting that NASA is pandering to the prevalent idea that red and orange colors should be associated with heat and warmth, and that blue colors should be thought of as "cold". And since the Sun is undoubtedly "warm", the NASA people probably said to themselves, well, let's color it orange, then, so that people understand that we are showing them the Sun.


A "more true" ultraviolet image of the Sun should probably be shown like this, as a black and white intensity map of the Sun:

latest_aia_131[1].gif
The Sun in ultraviolet at 131 Å. Credit: SDAC.

I found another black and white image of the Sun, a "magnetic map" of the Sun, with magnetic lines pointing away from the Earth shown as black, and magnetic lines pointing our way shown as white.



That picture does make you think of the Moon, doesn't it? 😁

Ann
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Re: APOD: Total Totality (2024 Apr 12)

Post by Christian G. » Fri Apr 12, 2024 12:33 pm

Chris Peterson wrote: Fri Apr 12, 2024 5:09 am
florid_snow wrote: Fri Apr 12, 2024 4:22 am I saw this eclipse and the bright pink prominences were stunning, and it got me reading about H alpha emission. And after some reading, I feel betrayed by every "H alpha" filtered photo of the sun I have seen. Because the prominences appeared obviously PINK to human eyes, doesn't that mean that H alpha filtered images should be colored for "accurate human eye view" as either bright pink if we're being chemically accurate for all the emission lines of H or at least deep red for just the particular filter for H alpha emission?

And yet NASA images and astrophotographers tend to filter everything as an orange-ish color. It is like they can't trust the public to accept anything but a camp fire type color for the sun. But the true color of Hydrogen doing it's emission is obviously pink, as we all saw with our own eyes. Some photographers have to be brave enough to color their images with a semi-accurate pink color, right?

Edit: some examples:

Fake color:
Image

Realistic color:
Image
Color is a physiological property, not a physical one. With a narrow wavelength, the hue is fixed but the color changes with intensity. The apparent color of H-alpha is determined by its intensity, as well as by any other colors mixed in with it. In the case of the eclipse, that means white light, which desaturates the deep red hue of H-alpha. If you view the Sun through an H-alpha filter, you will not see pink. You will see deep ruby red. Any image of an H-alpha source that is uncontaminated with other light should be processed to look red in its midtones, scaling towards warm white as it gets brighter and black as it gets darker.

The image you labeled "fake" is close to what the Sun looks like through my narrow band solar telescope. I've never seen anything like the one you label "realistic".

Indeed, to my eyes, the prominences in this eclipse were red. Not pink. Very similar to the color in today's APOD.
When I zoom in the APOD I do see the "pink" as intense red indeed; could the impression (shared by many it seems) of having seen pink instead simply come from a residual fraction of white light blending in with the deep red?

Worth noting: the author's name of this great APOD of the total eclipse is Daniel KORONA!

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Re: APOD: Total Totality (2024 Apr 12)

Post by Chris Peterson » Fri Apr 12, 2024 12:40 pm

Christian G. wrote: Fri Apr 12, 2024 12:33 pm When I zoom in the APOD I do see the "pink" as intense red indeed; could the impression (shared by many it seems) of having seen pink instead simply come from a residual fraction of white light blending in with the deep red?
Consider this image, which is exposed for the prominences, not the outer corona.
_
E7_48324p2.jpg
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Re: APOD: Total Totality (2024 Apr 12)

Post by wilddouglascounty » Fri Apr 12, 2024 1:20 pm

This is a fascinating discussion with so many things to consider ("consider" etymology, by the way, alludes to "looking toward the stars" con+sidere)! Perception emerges from the interaction between two or more objects, and as such is completely objective at its core and yet subjectively spreads out through the complexity of that interaction. This takes nothing at all away from it being firmly anchored in reality any more than the interaction of an object with mass interacts with the time space continuum by creating a distortion that we perceive as "gravity." My brain's processing of the light waves radiating from that lunarly isolated solar prominence, that travels through the atmosphere, a light layer of cirrus clouds, my 69 year old eye lens slightly clouded by a touch of cataract, onto my retina, then whisked back to my occipital lobe for complex calibration, contextualization and image building, flavored by memories and evolutionary, species-specific emphases, is no less objective than the reception of the light radiation from that same prominence landing on a CCD that has been calibrated for a specific wavelength only, ignoring all other parts of the spectrum. To try to then try to translate that CCD data to accurately approximate the complexity of the eye-brain processing is a bit of a fool's task, and falls short in the same way as, for instance, trying to describe a symphony to a mostly deaf person or an eclipse to someone whose view of that eclipse was obscured by clouds. My earlier point in the provided link is that photographic/digital imagery falls short of my perception of the eclipse because of its inability to process the light intensity I experienced with my eyes, which was vastly more impressive than any photograph I've seen.

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Re: APOD: Total Totality (2024 Apr 12)

Post by Chris Peterson » Fri Apr 12, 2024 1:25 pm

wilddouglascounty wrote: Fri Apr 12, 2024 1:20 pm This is a fascinating discussion with so many things to consider ("consider" etymology, by the way, alludes to "looking toward the stars" con+sidere)! Perception emerges from the interaction between two or more objects, and as such is completely objective at its core and yet subjectively spreads out through the complexity of that interaction. This takes nothing at all away from it being firmly anchored in reality any more than the interaction of an object with mass interacts with the time space continuum by creating a distortion that we perceive as "gravity." My brain's processing of the light waves radiating from that lunarly isolated solar prominence, that travels through the atmosphere, a light layer of cirrus clouds, my 69 year old eye lens slightly clouded by a touch of cataract, onto my retina, then whisked back to my occipital lobe for complex calibration, contextualization and image building, flavored by memories and evolutionary, species-specific emphases, is no less objective than the reception of the light radiation from that same prominence landing on a CCD that has been calibrated for a specific wavelength only, ignoring all other parts of the spectrum. To try to then try to translate that CCD data to accurately approximate the complexity of the eye-brain processing is a bit of a fool's task, and falls short in the same way as, for instance, trying to describe a symphony to a mostly deaf person or an eclipse to someone whose view of that eclipse was obscured by clouds. My earlier point in the provided link is that photographic/digital imagery falls short of my perception of the eclipse because of its inability to process the light intensity I experienced with my eyes, which was vastly more impressive than any photograph I've seen.
While your points are taken, I disagree with your assertion, "My brain's processing... is no less objective than the reception of the light radiation from that same prominence landing on a CCD..." The former is the very definition of subjective and the latter of objective!
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Re: APOD: Total Totality (2024 Apr 12)

Post by rwlott » Fri Apr 12, 2024 3:13 pm

wilddouglascounty wrote: Fri Apr 12, 2024 1:20 pm This is a fascinating discussion with so many things to consider ("consider" etymology, by the way, alludes to "looking toward the stars" con+sidere)!
As long as we're talking about etymology, I find the term "terrain" in today's explanation to be oddly jarring.

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Re: APOD: Total Totality (2024 Apr 12)

Post by Christian G. » Fri Apr 12, 2024 4:23 pm

wilddouglascounty wrote: Fri Apr 12, 2024 1:20 pm a fool's task, and falls short in the same way as, for instance, trying to describe a symphony to a mostly deaf person
I wonder what Beethoven would say about that!

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Re: APOD: Total Totality (2024 Apr 12)

Post by Chris Peterson » Fri Apr 12, 2024 4:44 pm

Christian G. wrote: Fri Apr 12, 2024 4:23 pm
wilddouglascounty wrote: Fri Apr 12, 2024 1:20 pm a fool's task, and falls short in the same way as, for instance, trying to describe a symphony to a mostly deaf person
I wonder what Beethoven would say about that!
Well, he didn't start out deaf. I'm sure he could "hear" the symphony simply by reading the score.
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Re: APOD: Total Totality (2024 Apr 12)

Post by Ann » Fri Apr 12, 2024 5:26 pm

Chris Peterson wrote: Fri Apr 12, 2024 12:40 pm
Christian G. wrote: Fri Apr 12, 2024 12:33 pm When I zoom in the APOD I do see the "pink" as intense red indeed; could the impression (shared by many it seems) of having seen pink instead simply come from a residual fraction of white light blending in with the deep red?
Consider this image, which is exposed for the prominences, not the outer corona.
_
Chris Petersons solar eclipse picture annotated.png

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Re: APOD: Total Totality (2024 Apr 12)

Post by Chris Peterson » Fri Apr 12, 2024 5:39 pm

Ann wrote: Fri Apr 12, 2024 5:26 pm
Chris Peterson wrote: Fri Apr 12, 2024 12:40 pm
Christian G. wrote: Fri Apr 12, 2024 12:33 pm When I zoom in the APOD I do see the "pink" as intense red indeed; could the impression (shared by many it seems) of having seen pink instead simply come from a residual fraction of white light blending in with the deep red?
Consider this image, which is exposed for the prominences, not the outer corona.
_

Chris Petersons solar eclipse picture annotated.png


Ann
Which illustrates what I discussed elsewhere. "Color" is not just hue, but hue and brightness. And as the brightness increases, the color shifts towards white... which means it desaturates. Pink is just desaturated red. As the lower prominence is brighter, it appears "pinker" than the dimmer prominence at the side.

(And, of course, it illustrates the subjective nature of color. I would still call the prominence at the bottom "red" as opposed to "pink", if those were my only two choices.)
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Re: APOD: Total Totality (2024 Apr 12)

Post by Chris Peterson » Fri Apr 12, 2024 6:30 pm

This is kind of fun, an animated version of what we see in today's APOD. Frames are 30 seconds apart. (Might have to click on it to see the animation... depends on your browser.)
_
prom_stack.gif
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Re: APOD: Total Totality (2024 Apr 12)

Post by Ann » Fri Apr 12, 2024 6:36 pm

Chris Peterson wrote: Fri Apr 12, 2024 5:39 pm
Ann wrote: Fri Apr 12, 2024 5:26 pm
Chris Peterson wrote: Fri Apr 12, 2024 12:40 pm

Consider this image, which is exposed for the prominences, not the outer corona.
_
Ann
Which illustrates what I discussed elsewhere. "Color" is not just hue, but hue and brightness. And as the brightness increases, the color shifts towards white... which means it desaturates. Pink is just desaturated red. As the lower prominence is brighter, it appears "pinker" than the dimmer prominence at the side.

(And, of course, it illustrates the subjective nature of color. I would still call the prominence at the bottom "red" as opposed to "pink", if those were my only two choices.)
Chris, you're Danish. In Danish, "pink" is "lyserød", which means, literally, "light red" or "desaturated red". In other words, to a Dane, pink and red are the same hue, and one is just more saturated than the other.

In Swedish, "pink" is "rosa", a word that is clearly derived from the noun "rose". We are obviously talking about a pink rose here, not a red one. In my opinion, Swedes think of pink and red as two distinct colors, not as saturated and desaturated versions of the same hue.


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Re: APOD: Total Totality (2024 Apr 12)

Post by johnnydeep » Fri Apr 12, 2024 6:41 pm

Chris Peterson wrote: Fri Apr 12, 2024 6:30 pm This is kind of fun, an animated version of what we see in today's APOD. Frames are 30 seconds apart. (Might have to click on it to see the animation... depends on your browser.)
_
prom_stack.gif
Very nice. So, that would mean that the total time represented in the APOD is about 4.5 minutes, which I believe is - probably - the length of totality here? But are Bailey Beads considered part of totality?

Also, I'm confused about the time order of the frames shown in the APOD. They certainly aren't increasing (or decreasing) from top left to lower right, are they? Are they alternating? If so, what's the correct order?
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Re: APOD: Total Totality (2024 Apr 12)

Post by Chris Peterson » Fri Apr 12, 2024 7:04 pm

johnnydeep wrote: Fri Apr 12, 2024 6:41 pm
Chris Peterson wrote: Fri Apr 12, 2024 6:30 pm This is kind of fun, an animated version of what we see in today's APOD. Frames are 30 seconds apart. (Might have to click on it to see the animation... depends on your browser.)
_
prom_stack.gif
Very nice. So, that would mean that the total time represented in the APOD is about 4.5 minutes, which I believe is - probably - the length of totality here? But are Bailey Beads considered part of totality?

Also, I'm confused about the time order of the frames shown in the APOD. They certainly aren't increasing (or decreasing) from top left to lower right, are they? Are they alternating? If so, what's the correct order?
There are 7 frames here, so that's 3 minutes. Totality at my location (near Evening Shade, Arkansas, 100 meters from the centerline) was 4:13. But totality had already started when I switched to the fast bracketed shots, so the first of it is missed here.

The Moon was moving east, so lower right to upper left (I was facing south). Here's the time series from my location.
_
aligned_1k_seq.jpg
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Re: APOD: Total Totality (2024 Apr 12)

Post by Ann » Fri Apr 12, 2024 7:16 pm

Chris Peterson wrote: Fri Apr 12, 2024 6:30 pm This is kind of fun, an animated version of what we see in today's APOD. Frames are 30 seconds apart. (Might have to click on it to see the animation... depends on your browser.)
_
prom_stack.gif
Indeed, that's kind of fun, Chris. I must admit that the hydrogen alpha-bright lower right limb turns into a very desaturated shade of pink as the brilliant white sunlight is leaking through.

Speaking about red and pink again. To me, a very distinct difference between red and pink is that red is "just red", whereas pink contains a bit of blue, too. And even a bit of green.

The RGB values of red, ███, are r=255, g=0 and b=0.

But consider hot pink, ███ whose RGB values are (255, 105, 180), and light pink, ███, (255, 182, 193).

I can't think of those shades of pink as desaturated versions of red. To me, a desaturated shade of red would be one that still contained no green or blue, but contained a lower value of red than 255. How about this color, ███, (204, 0, 0)?

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Re: APOD: Total Totality (2024 Apr 12)

Post by Chris Peterson » Fri Apr 12, 2024 7:28 pm

Ann wrote: Fri Apr 12, 2024 7:16 pm
Chris Peterson wrote: Fri Apr 12, 2024 6:30 pm This is kind of fun, an animated version of what we see in today's APOD. Frames are 30 seconds apart. (Might have to click on it to see the animation... depends on your browser.)
_
prom_stack.gif
Indeed, that's kind of fun, Chris. I must admit that the hydrogen alpha-bright lower right limb turns into a very desaturated shade of pink as the brilliant white sunlight is leaking through.

Speaking about red and pink again. To me, a very distinct difference between red and pink is that red is "just red", whereas pink contains a bit of blue, too. And even a bit of green.

The RGB values of red, ███, are r=255, g=0 and b=0.

But consider hot pink, ███ whose RGB values are (255, 105, 180), and light pink, ███, (255, 182, 193).

I can't think of those shades of pink as desaturated versions of red. To me, a desaturated shade of red would be one that still contained no green or blue, but contained a lower value of red than 255. How about this color, ███, (204, 0, 0)?

Ann
You just need to get a jumbo box of crayons and you'll know the names of those colors.
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Re: APOD: Total Totality (2024 Apr 12)

Post by johnnydeep » Fri Apr 12, 2024 7:31 pm

Chris Peterson wrote: Fri Apr 12, 2024 7:04 pm
johnnydeep wrote: Fri Apr 12, 2024 6:41 pm
Chris Peterson wrote: Fri Apr 12, 2024 6:30 pm This is kind of fun, an animated version of what we see in today's APOD. Frames are 30 seconds apart. (Might have to click on it to see the animation... depends on your browser.)
_
prom_stack.gif
Very nice. So, that would mean that the total time represented in the APOD is about 4.5 minutes, which I believe is - probably - the length of totality here? But are Bailey Beads considered part of totality?

Also, I'm confused about the time order of the frames shown in the APOD. They certainly aren't increasing (or decreasing) from top left to lower right, are they? Are they alternating? If so, what's the correct order?
There are 7 frames here, so that's 3 minutes. Totality at my location (near Evening Shade, Arkansas, 100 meters from the centerline) was 4:13. But totality had already started when I switched to the fast bracketed shots, so the first of it is missed here.

The Moon was moving east, so lower right to upper left (I was facing south). Here's the time series from my location.
_
aligned_1k_seq.jpg
This doesn't make sense to me. Only your central shot of totality would represent almost all the the frames in the APOD. That is, the APOD is only capturing the leading and trailing edges of the Moon slightly before and after totality, yes?
--
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Chris Peterson
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Re: APOD: Total Totality (2024 Apr 12)

Post by Chris Peterson » Fri Apr 12, 2024 7:37 pm

johnnydeep wrote: Fri Apr 12, 2024 7:31 pm
Chris Peterson wrote: Fri Apr 12, 2024 7:04 pm
johnnydeep wrote: Fri Apr 12, 2024 6:41 pm

Very nice. So, that would mean that the total time represented in the APOD is about 4.5 minutes, which I believe is - probably - the length of totality here? But are Bailey Beads considered part of totality?

Also, I'm confused about the time order of the frames shown in the APOD. They certainly aren't increasing (or decreasing) from top left to lower right, are they? Are they alternating? If so, what's the correct order?
There are 7 frames here, so that's 3 minutes. Totality at my location (near Evening Shade, Arkansas, 100 meters from the centerline) was 4:13. But totality had already started when I switched to the fast bracketed shots, so the first of it is missed here.

The Moon was moving east, so lower right to upper left (I was facing south). Here's the time series from my location.
_
aligned_1k_seq.jpg
This doesn't make sense to me. Only your central shot of totality would represent almost all the the frames in the APOD. That is, the APOD is only capturing the leading and trailing edges of the Moon slightly before and after totality, yes?
I think the APOD is just showing the beginning and end, with a series of closely timed frames. The middle... well, I think that's been fudged a little. The Moon was quite a bit larger than the Sun with the eclipse. I have images of all the prominences we see in the middle shot, but they were not all visible at the same time. I don't think it was possible to see that central, fully eclipsed Sun as we see it in the APOD, at any single moment of time. At least, not from the centerline where I was.
Chris

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johnnydeep
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Re: APOD: Total Totality (2024 Apr 12)

Post by johnnydeep » Fri Apr 12, 2024 9:27 pm

Chris Peterson wrote: Fri Apr 12, 2024 7:37 pm
johnnydeep wrote: Fri Apr 12, 2024 7:31 pm
Chris Peterson wrote: Fri Apr 12, 2024 7:04 pm
There are 7 frames here, so that's 3 minutes. Totality at my location (near Evening Shade, Arkansas, 100 meters from the centerline) was 4:13. But totality had already started when I switched to the fast bracketed shots, so the first of it is missed here.

The Moon was moving east, so lower right to upper left (I was facing south). Here's the time series from my location.
_
aligned_1k_seq.jpg
This doesn't make sense to me. Only your central shot of totality would represent almost all the the frames in the APOD. That is, the APOD is only capturing the leading and trailing edges of the Moon slightly before and after totality, yes?
I think the APOD is just showing the beginning and end, with a series of closely timed frames. The middle... well, I think that's been fudged a little. The Moon was quite a bit larger than the Sun with the eclipse. I have images of all the prominences we see in the middle shot, but they were not all visible at the same time. I don't think it was possible to see that central, fully eclipsed Sun as we see it in the APOD, at any single moment of time. At least, not from the centerline where I was.
Thanks. And I'm now quite embarrassed about how confused I was about the timing of these shots. Sometimes - perhaps often - I insist on trying to make things more complicated than they are!
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"To B̬̻̋̚o̞̮̚̚l̘̲̀᷾d̫͓᷅ͩḷ̯᷁ͮȳ͙᷊͠ Go......Beyond The F͇̤i̙̖e̤̟l̡͓d͈̹s̙͚ We Know."{ʲₒʰₙNYᵈₑᵉₚ}

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Re: APOD: Total Totality (2024 Apr 12)

Post by wilddouglascounty » Sat Apr 13, 2024 4:25 am

Chris Peterson wrote: Fri Apr 12, 2024 1:25 pm
wilddouglascounty wrote: Fri Apr 12, 2024 1:20 pm This is a fascinating discussion with so many things to consider ("consider" etymology, by the way, alludes to "looking toward the stars" con+sidere)! Perception emerges from the interaction between two or more objects, and as such is completely objective at its core and yet subjectively spreads out through the complexity of that interaction. This takes nothing at all away from it being firmly anchored in reality any more than the interaction of an object with mass interacts with the time space continuum by creating a distortion that we perceive as "gravity." My brain's processing of the light waves radiating from that lunarly isolated solar prominence, that travels through the atmosphere, a light layer of cirrus clouds, my 69 year old eye lens slightly clouded by a touch of cataract, onto my retina, then whisked back to my occipital lobe for complex calibration, contextualization and image building, flavored by memories and evolutionary, species-specific emphases, is no less objective than the reception of the light radiation from that same prominence landing on a CCD that has been calibrated for a specific wavelength only, ignoring all other parts of the spectrum. To try to then try to translate that CCD data to accurately approximate the complexity of the eye-brain processing is a bit of a fool's task, and falls short in the same way as, for instance, trying to describe a symphony to a mostly deaf person or an eclipse to someone whose view of that eclipse was obscured by clouds. My earlier point in the provided link is that photographic/digital imagery falls short of my perception of the eclipse because of its inability to process the light intensity I experienced with my eyes, which was vastly more impressive than any photograph I've seen.
While your points are taken, I disagree with your assertion, "My brain's processing... is no less objective than the reception of the light radiation from that same prominence landing on a CCD..." The former is the very definition of subjective and the latter of objective!

So each step toward "subjectivity" in the perceptual chain is an objectively measurable process, from the arrival of the photons from the prominence into the slightly clouded lens of my eye all the way to the responses of the neural networks from which my perception of that prominence emerges, agreed? So where does subjectivity emerge? Or is the term just another way of saying that the complexity of objective processes involved in perception exceeds our ability to describe it scientifically? "Magic" as an explanatory answer is roundly rejected by science, which asserts that there are solid material explanations for all physical phenomena. Perhaps the term "subjective" has a similar sloppiness to it, and it is science's job to pull back the curtain of complexity that it hides behind.