Why perfect collections arent perfect - my analysis

[Liete]

Ever wonder why even on the best mastered perfect collection show hints of pixelation? Well I think I have figured it out. A dvd-5 contains 4.7 GB of data, a dvd-9 contains 8.5 as we all know. It is a fact that on many perfect collections (im not saying all) official dvd's are done a 2 on 1 or a 2 on 3 ratio often the sources are single volume dvd-5's.

4.7 GB + 4.7 GB = 9.4 GB

Dvd-9 = 8.5 GB

data loss for 2 full dvd-5 on one dvd-9 = 900mb

It is a fact that the second layer of a dual layer disc cannot hold as much as the first, so putting 2-3 full dvd-5's on a dvd-9 requires a 10-25% compression. True this can be slightly reduced by cutting features, but this can only do so much.

The saying Dvd-9 can hold twice as much as a Dvd-5 is not at all true.

[Schultz]

Actually its really quite simple..

Mpeg compression is Lossy meaning that your recompressed video will Never be as good as the original.. Think of it as putting it through a copier the output is never as good as the original no matter how high resolution you get it will never be as good as the original.

And anyways more or so Perfect collections are because they are ripped from R1's and have good audio / sub quality and decent video.

[Liete]

I know I have alot of them, I was just saying why I thought so.

[Mantis421]

My whole take on it is yeah I have gotten one or two perfect collections that were just crap because of errors ect. For me it doesent matter so much if it is HK or R1 as long as I can get the whole set at once. I dont like the idea of buying a few episodes and then having to wait 1-2 months before you can buy alttle bit more. I go through series to quick to want to have the wait.

[gubi-gubi]

data loss for 2 full dvd-5 on one dvd-9 = 900mb

It is a fact that the second layer of a dual layer disc cannot hold as much as the first, so putting 2-3 full dvd-5's on a dvd-9 requires a 10-25% compression. True this can be slightly reduced by cutting features, but this can only do so much.

The saying Dvd-9 can hold twice as much as a Dvd-5 is not at all true.

Well the argument doesn't matter seeing as more often than not HKs have like 3 volumes on one dvd-9 and not 2. 9 episodes usually and alot of r1s have 3 eps a disc and stuff. Saying they are not perfect because of this is pointless seeing as they would only be perfect if they were direct rips without any reencoding. Like Schultz said they only loose quality when reencoded. You could reencode to a higher bitrate than the source and the copy would still look worse than the original.

[hakken]

Hold on - what *is* a perfect collection, and what makes it called perfect?

[Kiruyuki]

it is called perfect because it has perfect subtitles and it has a japanese and an english dub. Thats why it is called a perfect collection. The set doesn't have to have "perfect" video to be perfect. It all depends on people's opinions.

[Schultz]

Simple.. a perferct collection is one called that since it is ripped from R1's..

not ripped from japanese dvd's and had fansub scripts or HK originals placed on em..