Re: What are these white dots on a lunar photo?


"William Hamblen" <wrhamblen@xxxxxxxxxxx> wrote in message news:mp1uo2tuk8tu6r5ugoa007ouibn7a9saur@xxxxxxxxxx
| On 24 Dec 2006 12:37:53 -0800, zerge@xxxxxxxxxxx wrote:
|
| >http://www.lpi.usra.edu/resources/lunar_orbiter/bin/info.shtml?223
| >
| >Click on the picture. There's a lot of whit dots which are clearly some
| >sort of noise on the film. Does anybody know why these imperfections
| >appear?
|
| The imperfections are defects from developing the film. The Lunar
| Orbiters shot the pictures on film that was automatically developed on
| the spacecraft, then scanned electronically and transmitted to Earth.
| The film was a long roll transparency and the developer was contained
| in a long roll of material that was pressed against the film to
| develop it. The process was like developing a Polaroid picture. The
| development process wasn't foolproof and occasionally defects would
| appear on the developed images. That's the source of the white
| specks. The horizontal lines are from the scanning process.
|
| Bud
| --
| The night is just the shadow of the Earth.

Are you trying to tell us those pictures were taking during an eclipse?
I've often seen the moon at night when it isn't in Earth's shadow,
even if I am.



.

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