Commerical DVD v/s DV->DVD quality difference ?

[Movie-Maker]

Recently it was the first time I converted some of MiniDV video to DVD.
I did spend a lot of time, trial-and-error, observation, and some study trying to understand digital video, came up with the settings that give me the best possible quality. I used HCenc. and captured AVI from my Sony TRV30 camcorder (1ccd, 970k video pixels).

However, when I compare a commerical dvd - like a mainstream movie - to the home made dvd, the quality of the commerical dvd is far better, even if the bitrate and ql of the home made dvd is better than that of the commerical dvd.
Why is that so ? On close observation I noticed that the captured AVI itself is of inferior quality. In other words, I am not able to see any difference between the captured AVI and the encoded m2v. I guess that means the source itself is the weakest link ?

But what exactly about the source affects the quality ? Is it the compression of the digital data stored on the tape that is not good enough ? Or not enough resolution of the ccd ? Or number of ccds ?

[cd090580]

For quality there is a huge difference between a standard user dv camera at about 300 $ and a professional cinema camera at several thousands $ (or even more)

[Movie-Maker]

yes I realized that already. I guess I am asking what exactly are those differences ? What technical factors contribute to that difference in quality ?

[cd090580]

I think the first thing is the lenses quality and also the captor.
Movie cameras have also a very big set of lenses vs classic cameras with compact lenses which captures much less light.

Second is electronic quality and probably also the compression codec (maybe the movie is stored as uncompressed video ?)

[poisondeathray]

Consumer DV is usually 8bit depth, 720x480, 4:1:1 chroma (can be 4:2:0), 25mb/s

Pro DV can be 10bit depth, 1920x1080, 4:4:4, 440-880mb/s. Some studios even use 4K resolution I think, maybe edDV has more info

Here is some more info
http://en.wikipedia.org/wiki/Digital_cinematography

[Cornucopia]

Since DV (usually) has 4:1:1 and DVD has 4:2:0 subsampling, you're losing color resolution right there, above and beyond what has already been lost.
Plus, differences in Depth of Field, BIG DIFFERENCES in motion smoothness (most H'wood stuff is tripod, dolly/crane, steadicam stuff), differences in MUCH MORE EVEN lighting, lack of DCT blockiness in source for H'wood stuff, as well as the obvious one--24p framerate vs. 29.97i = much better bitrate savings pariticularly as pertains to motion.
Then there's the whole oversampling/downrezzing quality difference...

Scott

[edDV]

Further to Cornucopia, there are differences in every step of production to adapt to and optimize the technology.

First most DVD is sourced from 35mm film cameras not video until very recently. Exceptions are TV shows like Saturday Night Live.

Assuming a video camera, their lens is likely to price out in the $6K to $20K+ range. The 3x HD sensors will be 1/3" or larger and processor is more than a single chip design. They usually master and edit at higher resolution and bit rate than anticipated for release. Difficult and/or high motion scenes are hand tweaked over days to minimize artifacts and bit rate. Many frames get hand touch up.

A better comparison might be a news cam or a typical camera used for reality shows. Here is an example.
http://catalog2.panasonic.com/webapp/wcs/stores/servlet/ModelDetail?displayTab=O&store...odel=AJ-HDX900

Even with this $26K camera, they will always use lights and reflectors to balance scene contrast. Optimal video quality needs a limited contrast range. Use of fill lights to bring black level up is equally important to key lighting the talent.

Reality camera


Cinema HD 2kx1k camera with film style lens