hi all, I'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 The four big and bright radiators (one on the top of the crop, one in the middle -partly in shade - and two on the bottom of the crop) 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. 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 Can you find it without looking at the solution below? http://legault.perso.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. regards Thierry Legault www.astrophoto.fr At 23:38 22/03/2011, Ralf Vandebergh wrote: >Subject: STS-133 astronaut ground-based observation; Update 1: frame >processing into final result > > >Update 1: frame processing into final result > >Hi all, > >The image on the left side shows a part of the ISS with docked Space >Shuttle Discovery in approach at a distance of still over 400 >km. On the Port side we see a bright illuminated Payload Bay Door >from Discovery and the Shuttle Robotic Arm Canadarm-1 (SRMS). At >this point, Canadarm-2 (SSRMS), is weakly illuminated visible on the >other side near the Columbus Module. (the module itself is mainly in >shade). At the end of the Arm, STS-133 astronaut Steve Bowen is >performing a spacewalk and just pops into view here as a small spot. >As the distance reduces, about 20 seconds later, the small spot of >the astronaut has grown and looks better resolved. The apparant size >of the spacewalker seems comparable with the ExPRESS Logistics >Carrier (ELC) mounted on the truss. On the image we can also see the >newly, during the mission installed ELC-4 on the Starboard 3 truss. >Also the two armed Robot Dextre (Special Purpose Dexterous >Manipulator (SPDM), and the second Automated Transfer Vehicle > (ATV) can be seen on the image. > >For the full analysis see; http://www.startje.be//vieuw.php?qid=375025 > >Best regards, >Ralf Vandebergh > >[Non-text portions of this message have been removed] > > > >------------------------------------ > >Visit the Flagship website: >http://www.InsideKSC.com >Yahoo! Groups Links > ><*> To visit your group on the web, go to: > http://groups.yahoo.com/group/inside_ksc/ > ><*> Your email settings: > Individual Email | Traditional > ><*> To change settings online go to: > http://groups.yahoo.com/group/inside_ksc/join > (Yahoo! ID required) > ><*> To change settings via email: > inside_ksc-digest@yahoogroups.com > inside_ksc-fullfeatured@yahoogroups.com > ><*> To unsubscribe from this group, send an email to: > inside_ksc-unsubscribe@yahoogroups.com > ><*> Your use of Yahoo! Groups is subject to: > http://docs.yahoo.com/info/terms/ Thierry Legault www.astrophoto.fr _______________________________________________ Seesat-l mailing list http://mailman.satobs.org/mailman/listinfo/seesat-l
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