Reason why I ask, is : I have at this point only two digital copies of two separate Hollywood 'films' on my Harddrive .
The first is Blue Harvest ( Family Guy) which I loaded up Nov 07., it runs 47:36 and once loaded the startup (play) shows up in my windows media player and the slide bar across the bottom of the screen -I can access and slide the pointer to any where in the 47 min video. It shows as 556 MB . I was under the assumption that this video was now fully on my harddive .
Yet with the Dark Knight is 152:10 yet the MB is only 253MB !  ., and when activated and playback on my windows media player I can only watch it in real time, I can't slide the bar over to any particular spot of the movie as I can with Blue Harvest.
At first I thought maybe it was streaming to my PC, yet when I kill the cable signal to my modem the video is still playing..

So How does this digital copy work??

Digital copies vary from studio to studio.

The idea is to give you a digital copy of the film you bought on your DVD or Blu-ray that you can load onto your computer that you can watch without having to have the original disc. You can copy it to an ipod or other device, and like itunes downloads, ultimately stops at 5 computers or devices (and they must, in the case of itunes copies, share the same itunes account). Yes, DRM is the guiding tecnology.

The image is 640 x 480, again much like an itunes download. Theoretically they are giving you (for free) a download of a film you bought in another format (DVD or Blu-ray). They claim that there is no additional charge on your disc(s) for this, strictly an incentive to buy that package.

The 20th Century Fox colaboration with Apple seems to work very well. There are glitches reported with some of the Warner digital copies... that may be your problem with the Dark Knight. (I ought to double check mine -- I haven't yet -- I'll get back to you.)

They say they are trying to lessen the impact of unauthorized downloading and people making an infinite number of copies of their DVDs using HandBrake and other software. To quote a MacWorld article:

"Assuming your goal is to watch your own movies on your own devices, the Digital Copy feature is much more convenient than ripping a movie yourself using HandBrake, MacTheRipper, or other DVD-conversion utilities. Those programs require you to extract the content of the DVD and then convert that content to a compatible video file—both slow processes.
"The main advantage of HandBrake is that it lets you convert your DVDs to higher-quality versions; for example, for copying to an Apple TV for watching on an HDTV. But if that’s something you want to do, you can still do so using the standard DVD included in the Digital Copy package."

I hope this helps.

Some of the modern codecs (a codec decompresses the bytestream into the images of the movie) do have problems with seeking in the files from Media Player (really annoying)... they do compress better though (not annoying).

The resolution of the movie obviously also matters when it comes to file size - a file made for playback on a portable device will typically use much smaller resolution than one you intend to play back through a TV connected to the computer.

So my guess is that these movies are simply encoded with different codecs.

Quoting icefyre:

Quote:
Well, personally if you really want to be able to play the movie on your laptop without dragging the physical disc around with you... there are plenty of programs (some of them even free. Use google) to rip your movie to a digital format without relying on terrible quality that is provided on the disc.

So long as you don't copy it for someone who doesn't own the dvd, or distribute it... then you have not done anything wrong.

Quite frankly, if you paid good money for a DVD... you should be able to do whatever the heck you want with it for your own personal use.

Unfortunately, in some countries it is illegal to break the copy protection with the usual "tools", no matter for whatever reason (i.e. private backup).

Quoting icefyre:

Quote:
Really? That is so absurd. I can't understand what the harm is if you are viewing it yourself and you paid for a copy of the movie on dvd.

But I guess the law doesn't have to make sense, it can just be "the law"

Personally I don't keep digital copies, as there's no point for me... but I find that very strange that if you can prove you own the movie on dvd, why you can't have a digital copy.

While the making of a digital copy of DVD material for personal use/backup is still a grey area in the courts, cracking or hacking the DRM protection on a DVD, whether doing it yourself or using a 3rd party program, is a prosicutable crime in many countries .

Well there you go, I have learned something different today Thanks for taking the time to post the info guys 

Lucky for me, doesn't really effect me anyway... I prefer real DVDs to watch