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Re: filmscanners: Stellar ghosts and Nikon Coolscan IVED (LS40)
In a message dated 5/10/2001 3:20:02 AM EST, hlehto@oj287.astro.utu.fi writes:
> When I scan an image containing black sky and bright stellar images with a
> Nikon Coolscan IVED (=LS40) , then close to the edge of the field every
> bright (saturated) stellar image has a faint ghost image separated from
> the main image (by 20- 40 pixels). All the ghost images are on the
> "outside". These are not present in the center 1/3 by 1/3 of the field.
> Multiscanning with vuescan appears to make these features more striking
> because it reduces the background noise but not
> these images.
The CCD might be over-exposed near the star, causing CCD
charge bleeding. It might also be some kind of optical side effect.
Try turning off "Device|Auto exposure" and set "RGB exposure" to 1.0.
Regards,
Ed Hamrick
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