# 60i help

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### #1 Aaron Solomon

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Posted 01 January 2010 - 11:04 PM

Hi All,

I'm feeling rather dumb today and need to ask a basic question. Is 60i=30 frames per second? Does the 60 represent fields or frames? I'd always assumed that the 60i meant 60 frames per second but with interlaced scanning, but I just read something that made me think that the 60 refers to the fields. SOrry, again, I'm feeling dumb.

Thanks,
Aaron
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Posted 02 January 2010 - 12:22 AM

60i is 60 fields, interlaced, producing 30fps. It's s'ok we all have brain breakdowns.
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### #3 John Sprung

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Posted 02 January 2010 - 04:19 AM

It's 60 fields, and if it comes from a video camera, surprise, there are no frames. You can't just put two fields together to make a frame, because things move in the time it takes to get the scan to the same region in the picture.

-- J.S.
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### #4 Aaron Solomon

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Posted 02 January 2010 - 03:24 PM

Thanks guys. But then what about 24p and 30p? Aren't they 24 and 30 frames per second? I'm guessing it's cause they're progressive scanning and that allows all the scan lines to be reproduced to create one frame? And is 60i = 30p?

Thanks
Aaron
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### #5 John Sprung

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Posted 02 January 2010 - 11:57 PM

Yes, 24p and 30p are 24 and 30 frames per second. No, 60i is not equal to 30p, they're very different. "i" is fields, "p" is frames.

-- J.S.
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### #6 Thomas James

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Posted 03 January 2010 - 12:12 AM

Since no one watches analog televisions anymore 60i after deinterlacing is converted to 60 frames per second.
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### #7 John Sprung

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Posted 03 January 2010 - 02:06 AM

Since no one watches analog televisions anymore 60i after deinterlacing is converted to 60 frames per second.

True, but with the loss of resolution and the residual interlace artifacts. Interlace is like something you step in. The smell lingers no matter how well you try to scrape it off your shoe. ;-)

-- J.S.
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