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Old March 19th, 2004, 10:51 PM   #1
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in theory

Ok, here's my question. The Sony TRV900 and VX2000 both have 'progressive scan ccds' in their specs. So the camera itself must add some interlacing to the video, or add as it's recorded, right? So.....In theory....when you de-interlace with footage from these cameras, isn't that just like reverting back to the pure image before the interlace was added. So...in theory....when you de-interlace footage from these cameras, you should not encounter as many "jaggies" as you normally would?
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Old March 19th, 2004, 11:57 PM   #2
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I don't believe this to be true. As I've seen noted elsewhere, there is a class action lawsuit over Sony's designation of "progressive scan" on some models. I believe that the slow shutter speed feature seems like progressive scan, but IIRC it's just a line doubled frame. If they were true progressive scan CCDs, they would allow for progressive capture and lay down to tape. Those models are capturing a run-of-the-mill interlaced frame. Anyone with more tech info care to confirm?


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Old March 20th, 2004, 04:07 AM   #3
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well lets say it was a true progressive scan ccd, like some of the JVC models have and like the old optura pi....would the theory be true?
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Old March 20th, 2004, 06:42 AM   #4
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There is a technical document that has been referenced before on this forum that says CCDs are progressive scan devices. It goes on to say, after the CCD captures 481 lines, circuitry in the camcorder combines lines in buffers then outputs them as interlaced signals. Don't know if that answers your question or not.
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Old March 20th, 2004, 12:40 PM   #5
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The motion is captured progressively but is laid to tape as interlace. Otherwise it wouldn't be DV. The progressive motion signature is preserved in this process. In normal interlace recording, the two fields are recorded at different points in time, 1/60th of a second apart. In progressive, the two fields are recorded at the exact same time. It's still going to tape as interlaced (it wouldn't be recordable if it weren't), but there is no time difference between the two fields. Therefore the video frames are 1/30th of a second apart for a more pronounced motion judder, as opposed to the smoother 1/60th of a second apart of normal interlace. Hope this helps,
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