Why is DVD quality so poor?

I wonder if anyone can help me to understand why DVDs I create at home are such poor quality compared to the original footage and to commercial DVDs? I know the information has to be compressed and encoded, but surely this is also the case with commercial DVDs? Or do they have bigger capacity? Or better codecs? If so, is there any way to reach this professional quality?

I know that stuff shot on film is bound to look better, but I have TV shows on DVD that I know were shot on DVcam at best, and probably miniDV, yet the quality is as good as tape....

I am shooting on MiniDV, editing in Final Cut on a G5 PowerMac and outputting via iDVD and a superdrive or straight to a consumer DVD recorder, using DVD-R in both cases.

Well, there are several issues here. The first is that it is likely that you have the compression set too high. This quality issue is most likely due to trying to fit too much footage onto a single disk, and is the first place to look for these issues. I know that the Sony camcorders that record onto 5cm disks look appalling if you want more than 30 minutes per disk - it's like watching a realplayer encoded trailer for your actual video, it's that bad.

DVD-Rs are half the size of commercial DVDs. You need to get dual layer disks to hold the same amount of footage at the same quality, and not all burners support them. They only come in recordable (not rewritable) formats, and tend to be slower to burn than normal DVD-Rs.

Plus, remember that most commercial stuff is shot at a much higher resolution and then scaled down to standard-definition.

If the DVD looks worse than the footage you see while editing in FCP, then it's a compression issue. However, if it looks the same, and you're comparing your captured (in FCP) footage to a "real" release, it's simply because they have better gear and shot the show better. Sure a TV show may be shot on DVCAM, but the format of the tape means next to nothing in the end. Lets not forget the $50,000 worth of lighting gear, $15,000 cameras, and a crew of professionals that know how to use it all. Grabbing a DV cam from Best Buy and shooting with a crew of friends and whatever lighting you could find in your garage isn't going to produce anywhere near the same image quality, but for some reason, people getting into digital video always assume it's the tape or computer's fault that their productions don't look so great.

disciple said:

I wonder if anyone can help me to understand why DVDs I create at home are such poor quality compared to the original footage and to commercial DVDs? I know the information has to be compressed and encoded, but surely this is also the case with commercial DVDs? Or do they have bigger capacity? Or better codecs? If so, is there any way to reach this professional quality?

I know that stuff shot on film is bound to look better, but I have TV shows on DVD that I know were shot on DVcam at best, and probably miniDV, yet the quality is as good as tape....

I am shooting on MiniDV, editing in Final Cut on a G5 PowerMac and outputting via iDVD and a superdrive or straight to a consumer DVD recorder, using DVD-R in both cases.

Click to expand...

you problem is in compression. if correctly encoded mpeg2 is actually better looking than source DV. I know it may sound like BS, but it's true. proper mpeg compression eliminates graininess of DV and as a result image looks smoother.
what I suggest you to do is try not to exceed 45-50 minutes for DVD-R (4.7GB) and 110-115 min for DL DVD (that's without slideshows and extra stuff). If you use iDVd 6, go to preferences and choose "best quality" and specify type of a DVD-R (single or double layer).

I never had any complains about iDVD encode.

seinman said:

If the DVD looks worse than the footage you see while editing in FCP, then it's a compression issue. However, if it looks the same, and you're comparing your captured (in FCP) footage to a "real" release, it's simply because they have better gear and shot the show better. ... for some reason, people getting into digital video always assume it's the tape or computer's fault that their productions don't look so great.

Click to expand...

No-footage is nice and clean in edit - I'm not expecting miracles, just some fidelity to the original shoot!

Forgot to say it's the colour and movement that often suffer, rather than the resolution itself...everything becomes a bit 'jerky' and the sound sync sometimes seems to slip...

Jerky motion is often created by the field order getting switched. DV is bottom field first.

Encode your .m2v (mpeg-2) at around 7.8kbps and like someone said earlier, try to keep it about 50 minutes per 4.7GB DVD

Thanks all, that gives me food for thought, particularly thanks to those who were more gracious and less jump-to-conclusion-know-it-all in their responses!