Tony Phillip's reply follows...
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Don Pettit took this photo from the ISS. He used a digital camera. About
2/3 of the "stars" are from the camera. The true stars all have the same
smile-like shape caused by tracking error. The false stars are mostly a
single bright pixel. This is a common problem with digital cameras and long
exposures. Usually one can just subtract a black picture taken while the
camera was at the same temperature for the exact same number of
seconds. In this case, no such correction was made.
So the features you note are evidence of NO MANIPULATION of the image, not
the reverse.
Regards, Tony
At 04:45 PM 3/29/2003 +1100, Nick wrote:
>http://science.nasa.gov/ppod/
>
>Dear Tony/Ron
>
>I have some questions about the photo posted on this date. The photo
>appears to be a time exposure of an iridium flare, but close
>examination shows stars superimposed on the solar panels of the ISS.
>This suggests that the photo is a digital pastiche of two separate
>images, not a single "chance" photo as described. Given evidence for
>digital manipulation of the image, it loses its value. In fact, there
>is no evidence that this is not a terrestrial image of an Iridium flare
>superimposed on an in-orbit image of the solar panels.
>
>Can you please comment on the true origin and pedigree of this image?
>
>
> - Nick
>
Dr. Tony Phillips, editor
Science@NASA http://science.nasa.gov
SpaceWeather.com http://spaceweather.com
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