Whats the differance between blu-ray and dvd?

Question

Whats the differance between blu-ray and dvd?

Answer 1

I will add that in the real world for movie watching purposes it boils down to resolution. Standard DVD is a 480 lines progressive scan, while blu-ray is typically 1080p. So- it is almost like the difference between SDTV and HDTV.

Unfortunately only TVs made within the last 2 years or so support 1080p inputs- so make sure your TV supports 1080p (not just standard 1080i or 720p HD) before you take the plunge.

Answer 2

Both of the previous posters are correct, but I'll just add to what they said.  Due to the larger capacity of a blu-ray, studios can transfer picture and audio in an uncompressed format.  Due to the lack of space on a DVD, movies are compressed to fit in 9gb so you get "lossy" sound and digital "artifacts" in the picture.  With a blu-ray, you can get Dolby TrueHD or DTS-HD sound which is a "lossless" audio.  There is no compression which allows it to breathe a little better.  

From a picture perspective, the lack of compression allows for brighter, crisper images that sometimes can give a 3D "Pop" effect.  Seeing is believing, so go check out a demo at your local Best Buy.  

Someone else mentioned you need a 1080p screen to fully enjoy.  While this is true, you will notice an improved picture if you have a 720p or 1080i screen as well.  Normal DVDs are transferred in 480i (standard television definition), so blu-rays will always look better unless your watching on a 13" black and white television, you just won't be able to fully appreciate the disc.  

People also tend to forget about the sound improvements on blu-rays.  As I said, lossless audio (DTS-HD or TrueHD) can only be decoded on newer receivers, so if you're anything like me, then you may need to upgrade your home theater as well.  It gets to be a very expensive ordeal.

Answer 3

Mainly disc capacity. A standard DVD dual layer will hold 9 gigs of information. A Dual layer Blu Ray disc will hold 50 gigs of information, more than enough room for even a long movie AND all the bonus features you see on your normal 2 disc DVD release. These bonus features are often in 1080 resolution High Def as well.

  The reason the Blu Ray can hold so much information versus the Stadard DVD is the type of laser used. A standard DVD uses a red laser. The Blu Ray uses a blue laser (hence the name Blu Ray ;). Blue laser has a shorter wavelength than a red laser  and as such the same size disc can store more information in the same amount of space.

  Almost ALL Blu Ray players will also play standard DVDs. No standard DVD player will play a Blu Ray disc, they just do not have the capacity to read them.