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| 03:23 PM | ||
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| 03:23 PM | ||
"LOOK-NOW"---3 Days of Darkness Approach! NASA Stereo Behind HI1: 12/21/2012 it All Goes Dark! | |
Dr. Astro Senior Forum Moderator  User ID: 4211721  United States12/20/2012 06:28 PM  Report Abusive Post Report Copyright Violation | here's the darkest image from running the same parameters in the OP's post but back in 2011: Quoting: Silvanus [link to img195.imageshack.us] sorry I don't have a Gif editor on here... will start looking through previous years until i find something similar to compare. Again, that is not a beacon image. Notice how much the glare fluctuates over time: Again, I tried to compensate for it the best I could at that time without having to make a new calibration image each time the glare fluctuated, so I set the subtraction strength so that some of the images would be too bright, rather than the other images being too dark, but the actual amount of variation is the same thing you're seeing here.  |
| Dapurps User ID: 10064730  Canada12/20/2012 06:28 PM Report Abusive Post Report Copyright Violation | |
| Dr. Astro Senior Forum Moderator User ID: 4211721 United States12/20/2012 06:28 PM Report Abusive Post Report Copyright Violation | done, will upload in a minute. My 2 cents is it looks nothing like the current. Maybe some slight darkening but that's it. It doesn't work like that, they don't retaint he processed versions of the beacon images. That's what you're looking at in the current images. They only archive the raw originals. ok, do you know how often they are archived? That way it'll be easy to compare as soon as the current is archived since they will be in the same format as older archived footage. Correct? The latest raw beacon data is already archived, that's how I got this image: :behind122012: I didn't do any background subtraction on it though. |
| Dr. Astro Senior Forum Moderator User ID: 4211721 United States12/20/2012 06:30 PM Report Abusive Post Report Copyright Violation | Quoting: Dapurps Yup. When it hits the 18th the images are then BEACON images (lower quality). I just checked the FTP a little while ago and the latest non-BEACON images are from the 17th, so that's consistent with what I saw. |
| PhxRising User ID: 6245825 Canada12/20/2012 06:30 PM Report Abusive Post Report Copyright Violation | [link to www.youtube.com] From 2010, sun does a complete flip....watch 40 to 60 seconds of clip for best slow motion. If the sun can do this, then a '3 day darkness event' is only slightly more impressive. |
| Anonymous Coward User ID: 25755477 United States12/20/2012 06:31 PM Report Abusive Post Report Copyright Violation | |
| Anonymous Coward User ID: 24633315 United States12/20/2012 06:31 PM Report Abusive Post Report Copyright Violation | |
| Dapurps User ID: 10064730 Canada12/20/2012 06:31 PM Report Abusive Post Report Copyright Violation | Quoting: Dapurps Yup. When it hits the 18th the images are then BEACON images (lower quality). I just checked the FTP a little while ago and the latest non-BEACON images are from the 17th, so that's consistent with what I saw. Stoked to see your coverage tomorrow. Thanks for all the info "What you perceive to be becomes your reality." :ftwpanda: dapurps |
| Silvanus User ID: 30383281 Canada12/20/2012 06:32 PM Report Abusive Post Report Copyright Violation | quick question here, in watching the original animation, it seems there are alot of images up until the 17th and then only a few for the 18th forward when the blackening occurs.why iss this? Has anyone answered this yet? Just curious. Last Edited by LeisureLee on 12/20/2012 06:33 PM |
| Dapurps User ID: 10064730 Canada12/20/2012 06:34 PM Report Abusive Post Report Copyright Violation | quick question here, in watching the original animation, it seems there are alot of images up until the 17th and then only a few for the 18th forward when the blackening occurs.why iss this? Has anyone answered this yet? Just curious. Quoting: Silvanus Read thru what Astro has been saying. "What you perceive to be becomes your reality." :ftwpanda: dapurps |
| BOWTIE66 User ID: 28947704 United States12/20/2012 06:34 PM Report Abusive Post Report Copyright Violation | |
| pats User ID: 1452977  Bulgaria12/20/2012 06:37 PM  Report Abusive Post Report Copyright Violation | displayed only when the light disappear completely, perhaps a fault of the camera or dust on illuminator There are only 10 types of people: those who understand the binary system and those who do not understand it. |
| Anonymous Coward User ID: 29639471 United States12/20/2012 06:37 PM Report Abusive Post Report Copyright Violation | |
| Silvanus User ID: 30383281 Canada12/20/2012 06:39 PM Report Abusive Post Report Copyright Violation | quick question here, in watching the original animation, it seems there are alot of images up until the 17th and then only a few for the 18th forward when the blackening occurs.why iss this? Has anyone answered this yet? Just curious. Quoting: Silvanus Read thru what Astro has been saying. yes I have been, didn't see any explaination thats why i'm asking. |
| Dr. Astro Senior Forum Moderator User ID: 4211721 United States12/20/2012 06:39 PM Report Abusive Post Report Copyright Violation | quick question here, in watching the original animation, it seems there are alot of images up until the 17th and then only a few for the 18th forward when the blackening occurs. Has anyone answered this yet? Just curious. Quoting: Silvanus Beacon images are always fewer in number than regular images. Coverage is dependent on who's available, which varies since it involves amateur contributions. DSN can also provide support, but they have many other missions to support whose data takes priority. "The near-real-time data, known as the Space Weather Beacon, from STEREO is a compressed, binned, subset of the full science data. The beacon data are broadcast continuously, and if no ground station is listening, the data will not be available until the full science data is dumped." [link to www.swpc.noaa.gov] |
| Anonymous Coward User ID: 7813501 United States12/20/2012 06:40 PM Report Abusive Post Report Copyright Violation | |
| Silvanus User ID: 30383281 Canada12/20/2012 06:41 PM Report Abusive Post Report Copyright Violation | quick question here, in watching the original animation, it seems there are alot of images up until the 17th and then only a few for the 18th forward when the blackening occurs. Has anyone answered this yet? Just curious. Quoting: Silvanus Beacon images are always fewer in number than regular images. Coverage is dependent on who's available, which varies since it involves amateur contributions. DSN can also provide support, but they have many other missions to support whose data takes priority. "The near-real-time data, known as the Space Weather Beacon, from STEREO is a compressed, binned, subset of the full science data. The beacon data are broadcast continuously, and if no ground station is listening, the data will not be available until the full science data is dumped." [link to www.swpc.noaa.gov] awesome, thanks. |
| Dr. Astro Senior Forum Moderator User ID: 4211721 United States12/20/2012 06:41 PM Report Abusive Post Report Copyright Violation | Yup, basically says what I've been saying: [link to stereo.gsfc.nasa.gov] |
| Anonymous Coward User ID: 26463917  United Kingdom12/20/2012 06:42 PM Report Abusive Post Report Copyright Violation | [link to www.youtube.com] Quoting: PhxRising From 2010, sun does a complete flip....watch 40 to 60 seconds of clip for best slow motion. If the sun can do this, then a '3 day darkness event' is only slightly more impressive. The sun does not flip.. Cameras flip. |
| Anonymous Coward User ID: 1352760 Canada12/20/2012 06:44 PM Report Abusive Post Report Copyright Violation | If you people REALLY believed this was going to happen you would not be wasting time on this board. Quoting: mikebo2 You would be taking your necessary belongings to your bunker or hideout. Please explain why you are wasting time talking about it? listen I told my wife not to take her mother in there and if she did I wasnt coming with em .So now for me its kind of a win win situation 1- if shit hits the fan I wont have to survive with the mother in law 2- if nothing happens I am going to fire up my excavator and walk it all around the bunker occassionaly slamming my bucket on the ground to give em a scare , then after they freak out for a couple days I will let them out in time for christmas see - win win cheers and merry hoho to all |
| biscuits and gravy (OP) User ID: 1072087 United States12/20/2012 06:44 PM Report Abusive Post Report Copyright Violation | |
| The 6th Sun User ID: 25121342 United States12/20/2012 06:46 PM Report Abusive Post Report Copyright Violation | What was that? Is there a recording of this? Thread: ARE THEY GOING TO CRASH THE INTERNET? Thread: They have taken over our Constitution via UCC and here is how they did it! "God sleeps in the rocks, stirs in the plants, dreams in the animals, and finally awakens in man." -Famous Vedic Quote- [link to youtu.be] |
| Mwalk Low Earth Orbit User ID: 1067150 United States12/20/2012 06:47 PM  Report Abusive Post Report Copyright Violation | You're what the French call "les incompetents" ... Last Edited by M*walk on 12/20/2012 06:47 PM “The tree of liberty must be refreshed from time to time with the blood of patriots and tyrants.” |
| Anonymous Coward User ID: 7813501 United States12/20/2012 06:49 PM Report Abusive Post Report Copyright Violation | |
| biscuits and gravy (OP) User ID: 1072087 United States12/20/2012 06:49 PM Report Abusive Post Report Copyright Violation | |
| Anonymous Coward User ID: 30420838 United States12/20/2012 06:49 PM Report Abusive Post Report Copyright Violation | Processing artifact from the background subtraction they're using. They usually average a previous day's images together to create a calibration image which is subtracted from the latest image so that they can elminate the glare from the sun and see the tenuous heliosphere. They only update the calibration image every so often, and as time passes it may become less and less appropriate compared to the actual glare that's present and how the CCD is responding to the light. In other words, the calibration image is currently subtracting too much. There isn't really a "dark" region there, it's actually quite bright and if you don't compensate for it and try to just adjust the levels of the raw unprocessed beacon image to match the JPGs present online you end up blowing out the glare which is what you see with the large white region on the left side of the image: :behind122012: It seems like the calibration image they're using for the non-BEACON images is much better right now (high quality low compression versions of the same images), which is why if you go back a few days the problem vanishes instantly. Once you step forward one image into the BEACON images the problem with the calibration frame appears. In a few days when you check back at the stereo site, the beacon JPGs will be replaced with full resolution JPGs from the non-BEACON versions, at which time the "black region" will probably either be greatly reduced or gone altogether. Standard non-BEACON images have to be processed from scratch so just because there's a problem with the BEACON processed version does not always mean there will be a problem with the full res version a few days later. You are literally saying that the glare from the sun has subsided beyond established non-BEACON glare-reducing image processing parameters resulting in the recent darkened STEREO images. Presumably, glare is a direct function of sun luminosity, which would mean that the sun has darkened beyond established image correcting parameters. This begs the question: is this level of darkening unusual? If so, to what quantitative degree? The amount of glare is subject to a number of variables including the brightness of the sun (which varies with the presence or absence of sunspots), the spacecraft attitude, and the response of the CCD to light. So no, it's not a direct function of solar luminosity, that is only one component. Yes, solar irradiance is variable, but the amount of variation is quite small in amplitude, about .1~.3% : [link to blogs.edf.org] When processing these images, adjusting the strength of the background subtraction by even that very small percentage can have a large impact on the result - the processing includes a lot of aggressive contrast enhancement so even tiny differences are exaggerated. Having done a lot of STEREO HI image processing myself, I know for a fact it's quite normal for the amount of glare to change over time which can result in artifically bright or dark regions in the image. In fact, it's why I started developing my own processing method which doesn't involve subtracting previous images but rather involves a dynamic background subtraction using only the current image: Thanks again for taking the time to answer these questions in a civil and rational manner. |
| Anonymous Coward User ID: 13184694 United States12/20/2012 06:50 PM Report Abusive Post Report Copyright Violation | |
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| biscuits and gravy (OP) User ID: 1072087 United States12/20/2012 06:51 PM Report Abusive Post Report Copyright Violation | |
