Yes, Astronauts and robots inside of vehicles are not visible, this is not a helpful addition to your point. I can't tell whether you are failing to be funny, or just being snide, but this is obvious to everyone. The robot arm is not inside the ISS, I don't get it. I don't understand why you would say an astronaut is "smaller at this scale". Please explain your ratios. An astronaut in his white suit at 300Km distant is about the same angular size as any of Jupiter's ~4000Km diameter satellites, being ~600 million kilometers away. The astronaut is also some 40 times more brightly lit and dressed in white, and space is nearly black. So signal to noise is at *least* 40 times better. This isn't an issue of faith, it's simple math. Or maybe you think Galileo just "Wanted to believe" too? Of course his optics were dismal compared to ANY modern telescope. -Paul -----Original Message----- From: seesat-l-bounces+paulgrace=lookoutranch.com@satobs.org [mailto:seesat-l-bounces+paulgrace=lookoutranch.com@satobs.org] On Behalf Of Thierry Legault Sent: Thursday, April 21, 2011 11:41 To: SeeSat-L@satobs.org Subject: RE: A person and a Robot seen from Earth! hello Paul, my replies are inserted in your text At 01:28 20/04/2011, Paul Grace wrote: >Mr. Legault, I am not expressing an opinion on the photos, as I have not >traced their acquisition. However, your composite image isn't a reasonable >test comparison. For one, the "astronaut" image was shown in silhouette, >sunlight-lit, against black space. Your image is not similar. both spacewalkers were visible, from the ground, as bright silhouettes against black space, so the situation is similar. Anyway, I pointed out my image mainly to show how the elements of the ISS look like in reality, without artefacts and distortions, for example the square shape of the structures of the radiators (the brightest parts of the ISS). In addition, as it is possible to diagnose a flu without needing to know where and when the patient has caught it, I do not need to trace the acquisition of this image to make these findings. It's a processed image that is proposed to us and that is supposed to show an astronaut and a robotic arm, so it's sufficient in itself, even if I agree that seeing the raw image and knowing the process would help us to confirm the findings. >Second, from mission logs, the location of an astronaut on the ISS and the >silhouette of the ISS during spacewalk can be determined, and compared to >the imagery for confirmation. I agree, but this is far from sufficient since one can always find one image amongst hundreds that can show what he wants to see, with the help of noise, turbulence distortions and speckles and excessive processing. On this page ( http://legault.perso.sfr.fr/bad_astrophotography.html ), the fact that I have one image of Vega that looks like Soyuz does not prove that I really captured the structures of this spacecraft. You have to add two mandatory conditions: - the other ISS structures of similar or larger size than an astronaut and a robotic arm shall be visible and recognizable - the image shall be free of artefacts (i.e. "structures" that do not exist in reality) The image proposed here does not fulfill at all these two conditions, as a comparison with my image easily demonstrates. >Third, Comparing the silhouette of a two-meter astronaut three hundred >kilometers away to the details of the surface of a Jovian satellite >600*10^6km away seems equally misplaced, as comparatively, the astronaut is >roughly the same size as Io, Europa, or Callisto (Hardly a "detail"). At the (relatively large) scale of the smallest real details of this image, once removed the noise and the artefacts, an astronaut would be a detail since it is smaller than this scale. >Finally, although I could be mistaken, the image could be a composite of >several frames, and that could dramatically improve S/N, resolution, and >color, in the result. Distortions and artefacts clearly demonstrate that this processed image cannot originate from a composition of several frames, otherwise the radiators would show square structures (with possibly soft edges and round corners, depending on the true resolution) but not these complex and distorted shapes. It comes from a single raw image and all serious imagers know that a compressed 8-bit raw image is not reliable and cannot be processed without leading to strong noise and artefacts. Here, the appearance of the processed image demonstrate that the raw image has been enlarged and processed so that noise is transformed into something that may look like details to an untrained eye (fyi, my processed images are a combination of 15 raw, uncompressed 12-bit images and their processing is only a slight sharpening). >It is up to the author of the photos to explain the methodology, and if he >does not, then we need not accept any particular conclusions. But >suggesting the image cannot be what it purports to be seems unhelpful. Paul, I agree that the methodology would be very interesting if we could know it, but even without it what I'm saying is not suggestions, it's fact and findings supported by evidences. Let's call a spade a spade: an image that is not even able to show correctly such big structures as the radiators ones is far from having the quality required to record an astronaut at the end of a robotic arm, except perhaps for a follower of "I want to believe". Not more that it shows "a robot seen from Earth", since this robot is inside the ISS and the ISS does not have transparent walls ;-) >-----Original Message----- >From: seesat-l-bounces+paulgrace=lookoutranch.com@satobs.org >[mailto:seesat-l-bounces+paulgrace=lookoutranch.com@satobs.org] On Behalf Of >Thierry Legault >Sent: Tuesday, April 19, 2011 13:58 >To: SeeSat-L@satobs.org >Subject: Re: A person and a Robot seen from Earth! > > >hello, 'm not sure if it's necessary to underline this fact because I >know that members of this list are already conscious of it, but one >cannot rely on a single raw image to show details at instrumental >limits. What is pointed out in this image can be anything else than >an astronaut and a robotic arm, and especially noise and/or >distortion caused by turbulence, as I illustrated on this page: ><http://legault.perso.sfr.fr/bad_astrophotography.html>http://legault.perso . >sfr.fr/bad_astrophotography.html > >The four big and bright radiators are rectangular, with structures >inside that are also rectangular (like chocolate bar) and much bigger >than an astronaut. Nevertheless, on this image they look strongly >distorted and their edges are fuzzy. Many elements along the ISS >modules, many of them much bigger than an astronaut and a robotic >arm, are distorted, hardly recognizable or even not visible at all, >such as details at the end of Colombus. This is the case even for >Discovery, the ATV and the Soyuz themselves, despite their size. On >the contrary, many "details" visible on this image do not exist at all. > >Another evidence is that an image supposed to resolve details at the >limit of instrumental capability shall show diffraction effects, >under the form of variations of the Airy pattern: diffraction rings >around bright spots and diffraction lines along bright lines. But >this image does not show such effect at all. In addition, at this >supposed level of details, a "real color" processing is meaningless >since several pixels are necessary to show real color of each detail, >because of the Bayer matrix. > >In the following picture of the ISS, where you can see the real >shapes of the radiators and other elements, I have superimposed an >astronaut somewhere: ><http://legault.perso.sfr.fr/iss_astronaut.jpg>http://legault.perso.sfr.fr/ i >ss_astronaut.jpg >Can you find it without looking at the solution below? ><http://legault.perso.sfr.fr/iss_astronaut_solution.jpg>http://legault.pers o >.sfr.fr/iss_astronaut_solution.jpg >This comparison helps to realize the level of sharpness really needed >to show an astronaut. > >In short, I am sorry to say that this image is far from having the >sharpness and resolution necessary to show an astronaut and the >robotic arm, exactly as an image of Jupiter that hardly shows the >Great Red Spot is unable to show details on its satellites. > >For those who want to know how looks like the ISS in reality, I >recall that they can have a look at my last images and video >sequences: ><http://legault.perso.sfr.fr/STS-133.html>http://legault.perso.sfr.fr/STS-1 3 >3.html > >regards > > >At 15:14 12/04/2011, Ralf Vandebergh wrote: > > >Subject: A person and a Robot seen from Earth! > > > >Special for todays 50 years Human in Space; A PERSON & A ROBOT seen > >from Earth. Since Yuri Gagarin, we have accomplished quite > >something. An even more Human-like robot was brought with to the > >ISS, but this one is inside (Robonaut). > >This result is one of my best resolution ISS images so far. The > >image shows also resolved detail within Robot Dextre and the ELC > >elements. Dextre (SPDM) is here still visible at its old location, > >before it was grappled by the Canadarm-2 later, see the other image sent >today. > > > >http://www.startje.be//vieuw.php?qid=375025 > > > > > >Ralf Vandebergh > >Thierry Legault >www.astrophoto.fr > > >_______________________________________________ >Seesat-l mailing list >http://mailman.satobs.org/mailman/listinfo/seesat-l > >_______________________________________________ >Seesat-l mailing list >http://mailman.satobs.org/mailman/listinfo/seesat-l Thierry Legault www.astrophoto.fr _______________________________________________ Seesat-l mailing list http://mailman.satobs.org/mailman/listinfo/seesat-l _______________________________________________ Seesat-l mailing list http://mailman.satobs.org/mailman/listinfo/seesat-l
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