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| Sagittarius A* |
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| TimFox:
No, that is "Rorschach". I also know what "wank" means. I'm not surprised to see a forged image on YouTube. See section 5 of the paper I cited which discusses the reconstructed images. By the way, you seem to agree with Einstein, who in 1939 also found black hole solutions to his GR equations disturbing, dare I say "icky"? https://www.jstor.org/stable/1968902?seq=1#page_scan_tab_contents |
| aetherist:
--- Quote from: eugene on May 13, 2022, 03:37:03 pm --- --- Quote from: aetherist on May 12, 2022, 10:53:14 pm ---https://www.space.com/webb-flaring-milky-way-black-hole JamesWebb probly wont be able to make a good image. But at least its image will be a true image, not a math rorscharch wankfest. https://en.wikipedia.org/wiki/Rorschach_testre-creation . --- End quote --- You can define "true image" any way that pleases you. Just be aware that other people might disagree. Do that often enough and others will stop paying attention to you. --- End quote --- Cosmologists & JamesWebb & Co use artificial colour etc, that’s ok. Creating a 100,000 pixel image from say 5 pixel info is i think a long ways away from being a true image, but others might disagree. |
| TimFox:
--- Quote from: aetherist on May 13, 2022, 09:24:45 pm --- --- Quote from: eugene on May 13, 2022, 03:37:03 pm --- --- Quote from: aetherist on May 12, 2022, 10:53:14 pm ---https://www.space.com/webb-flaring-milky-way-black-hole JamesWebb probly wont be able to make a good image. But at least its image will be a true image, not a math rorscharch wankfest. https://en.wikipedia.org/wiki/Rorschach_testre-creation . --- End quote --- You can define "true image" any way that pleases you. Just be aware that other people might disagree. Do that often enough and others will stop paying attention to you. --- End quote --- Cosmologists & JamesWebb & Co use artificial colour etc, that’s ok. Creating a 100,000 pixel image from say 5 pixel info is i think a long ways away from being a true image, but others might disagree. --- End quote --- Read section 3 to see how the authors crunched the data. There is a lot of discussion of statistical methods to generate a best estimate, using different approaches to compare results. This is not hand-waving. Have you ever done maximum-likelihood data processing? Are you familiar with the concepts of resolution and pixel? A pixel is the quantization of the display, and very often is finer than the actual resolution. In general, it wastes whatever resolution you have to display it with coarser pixels. I often digitize my (non-periodic) 4x5 inch film images at 2400 dots/inch, to not lose resolution in that process, which takes forever. |
| raptor1956:
Every consumer digital camera in use today makes use of math to reconstruct the image. When taking still images the data is expressed in a Bayer pattern and demosaicing, a mathematical process, must be done to reconstruct the image. An even more complex process is involved with video as the enormous data rate is way too high for consumer cameras to handle uncompressed. Math is required for everyday images and video and anyone that uses digital cameras knows that the end result is an accurate representation of what the photographer was shooting, given limitations of exposure and technique. A more direct comparison to the methods used to capture the BH image is the interferometric approach needed to combine the images captured by telescope using multiple imagers or when multiple telescopes are combined. The VLT is a four telescope installation that can use each telescope independently or they can be combined using interferometry. The techniques used to capture an image of Sag A* is simply an extension of techniques already in use everyday. I'm disturbed that we have a member that has his head up his, well, black hole, and fawns over a YT charlatan! Brian |
| TimFox:
Yes, long before current interferometry with Earth-dimension long baselines, "regular" interferometers were used (in 1920) to measure the disc diameter of distant stars, which could not be resolved directly with telescope optics. https://en.wikipedia.org/wiki/Michelson_stellar_interferometer |
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