Posted by GMAN on 07/11/06 16:42

In article <lb74b252qk6im2fbcukpb02do91k8qrgga@4ax.com>, Martin Heffels <youwishyouwouldknow@nottellinya.com> wrote:
>On 9 Jul 2006 17:35:07 -0700, ptravel@travelersvideo.com wrote:
>
>>Absolutely not. There is a slight possibility of data drop out, as
>>there is with any digital storage medium (and that possiblity is
>>extremely rare). There is, however, no generational loss.
>
>Data drop-out is the equivalent of generation-loss in digital duplication.
>Of course, the laywer that you are, we are going to have a semantics battle
>about this :-) But I use it in terms of popular semantics, which is not
>always strictly correct for those who follow the letter of the law :-)
>
>>
>>>
>>> >> Doubt it. I do remember one test involving multiple generations of
>>> >> recompression of DV footage which claimed degradation after about 18
>>> >> generations, but you shouldn't see serious issues when making digital
>>> >> copies. You're likely to have the odd dropout on the tape, but
>>> >> otherwise the general quality should be fine.
>>> >
>>> >You're correct that the there will be no generation loss. However,
> drop-out
>>> >from digital video tape is very, very rare.
>>>
>>> Not correct. This solely depends on the quality of the codecs used.
>>
>>Look up the meaning of drop out. It has nothing to do with codecs.
>
>We were talking about generation-loss from multiple recompression. A couple
>of years ago I tried this with the MS-DV25 codec, and after the second
>recompression, you already saw some serious loss in quality. The MS-DV25
>codec has improved tremendously by now, but it still can't hold up a candle
>to the ones of Canopus and Matrox.
>
>>

There shouldnt be any recompression going on if one is just moving DV from one
device to another. Of course if any transitions or any type of editing is
done then yes you will see some slight reduction in quality over multiple
generations. But even this is sometimes at a minimun due to software using
smart rendering where only the parts that are edited are rendered.

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