I would like to ask about the difference in quality between R1 and R3 DVDs, in terms of both visual and sound effect. How big is the difference? People say it is great.

If really so, what makes the difference? Aren't they just copying digital datas? How come there would be such difference in quality?
(Even when the packages are exactly the same)
I really wanna know.

Sorry for not putting it in Chinese, but you guys pls feel free to do it in Chinese.