Op 16-8-2011 23:30, Mike McCants schreef: > There is a pretty image of a pass of NanoSail-D on the > web pages of Becky Ramotowski: > > http://astrobeck.com/2011/08/15/nanosail-d/ [snip] > It appears to me that there is some variation in the brightness > of the flashes in the first half (left) of the image and that > there is less variation in the brightness in the right half. Mike, That could be due to saturation of the trail in the right half - I have that problem with Nanosail-D during the brighter parts of it's passes - it is too bright!. Basically, the signal is clipped at a pixel value near 255 and you loose brightness variation that visually is very apparent but photographically is clipped out. In addition, this appears to be a quite reduced version of an image that in reality is much larger. Take heed there - strong reduction can mess things up, as large numbers of pixels have to be averaged. This can actually even produce "brightness variation" that is not there in reality but introduced by the pixel interpolation during reduction! - Marco ----- Dr Marco Langbroek - SatTrackCam Leiden, the Netherlands. e-mail: sattrackcam@wanadoo.nl Cospar 4353 (Leiden): 52.15412 N, 4.49081 E (WGS84), +0 m ASL Cospar 4354 (De Wilck): 52.11685 N, 4.56016 E (WGS84), -2 m ASL SatTrackCam: http://home.wanadoo.nl/marco.langbroek/satcam.html Station (b)log: http://sattrackcam.blogspot.com ----- _______________________________________________ Seesat-l mailing list http://mailman.satobs.org/mailman/listinfo/seesat-l
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