Full Moon Crossing (APOD 14 Oct 2006)

Comments and questions about the APOD on the main view screen.
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Andy Wade
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Full Moon Crossing (APOD 14 Oct 2006)

Post by Andy Wade » Sun Oct 15, 2006 12:59 pm

http://antwrp.gsfc.nasa.gov/apod/ap061014.html

Great picture. But could someone explain why they say this image is made from 6 video frames, but there are 11 full or part images of the International Space Station in the picture?
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Andy.

craterchains
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Post by craterchains » Sun Oct 15, 2006 1:16 pm

Yes, that is a good question.

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iamlucky13
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Post by iamlucky13 » Tue Oct 17, 2006 10:58 pm

Apparently each frame from his video camera is two exposures. I'm not sure why that is, but perhaps some videophiles can provide the answer. I found this in one of the links off the APOD:
The composite image above consists of 6 frames (12 fields) with the ISS moving right to left.
It seems the page was posted by the gentleman who took the images. It's worth taking a look at, especially since he has the video also posted.
http://pictures.ed-morana.com/ISSTransits/
"Any man whose errors take ten years to correct is quite a man." ~J. Robert Oppenheimer (speaking about Albert Einstein)

tvkrys
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Post by tvkrys » Thu Oct 19, 2006 1:49 am

Don't know what kind of camera he has, but way back in the time of analog video :D , your television picture was created using NTSC color standards. There are 525 lines displayed in a frame of analog video. Each frame of video has two fields and they are "interlaced". This means that all the even lines of video were on one field and all the odd lines of video were another field...
Krys
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