Separate names with a comma.
Discussion in 'Archived Threads 2001-2004' started by BrianGC, Feb 15, 2003.
Which DVD players have no layer change pause and also no chroma bug?
Brian you looking for some 23 century technology to be present in the 21st century, laser must 'swing' inwards from how far out it went. Unless you can buy a light speed 'pause' your going to be disappointed when you find out that I am correct.
Brian the disc plays from the center outwards, the laser beam must lift and go back to center lower to start reading 2nd layer. What can I say it doesn't operate like a 3.06 GHz computer. At this time we are talking about a 9.6+ GHz red lasered read only disc. I said those words no to confuse you with a ROM (Remember Only Memory~that are used by computers.
If DVD player makers really wanted to, they could make players that had no layer change pause. They would just have to add sufficient buffer memory to cover the length of the worst case pause condidtion: the laser mechanism moving full stroke.
This would add a little to the cost but could be a worthwhile marketing point.
The choroma bug has been sufficiently documented for long enough that any company who wanted to could easily produce a choma bug-free player. I suspect that there is not sufficient consumer demand for chroma bug-free players so the player makers or chipset makers generally place a lower priority on chroma bug avoidance than on the latest bells and whistles.
"laser must 'swing' inwards from how far out it went."
Nope, dual layered disc use opposith path tracking, meaning that there is just a focus change at the layer switch.
I still wonder about this. Part of the DVD specification to use the format for set-top players says that players cannot retain any of the video information in internal memory.
The spec seems to be designed so that players can't rip films to internal storage- but I've talked to some people who site the wording of this rule as why we don't have buffered players.
Brian, I can't vouch for the accuracy of this list but
here is a list about the chroma bug you may find useful.
Espen described what my understanding of the dual layer setup is. I've seen some posts where people mentioned the layer change pause and was just wondering which refocused the fastest.
I'll check that chroma-free list.
Just look here at the Shootout 3 results:
The 2nd column from the far right shows layer change times. I have the Denon 3800 and see no layer changes at all, even though in the column it says ".5" seconds. My DVD's play all the way through smoothly without interruption just like a SAT channel or cable channel movie or a VCR movie.
For "no chroma bug" players I believe you have to read the verbage for each player where they talk about each one having, or not having, the chroma upsampling error.
Very, very few players have both no noticeable layer change and no chroma upsampling error. The Denon 3800, Denon 9000, Krell DVD Standard, and CH-DVD 500 are just about the only ones tested during Shootout 3, but there may be a few more in existence not tested, of course, that meet both criteria you mentioned.
.5 is 'as good as it gets'!
The layer change is equal to 4 frames.
At 24 frames a second, that's 1/6 of a second.
Probably the best will 'ever' see [pun intended] is in the neighborhood of 1/4 [.25] of a second.
As we mention in the guide to the shootout, the disc we use to test layer change is designed to have the worst layer change possible. So in practice, the layer changes you'll see on movies will almost always be shorter.
Espen, my understanding is that while it is possible to have the second layer spiral in from the edge (thereby making the layer change faster), very few companies actually do it, because it's trickier to master properly. According to a friend who's knowledgeable about disc mastering, almost all discs have a second layer that spirals out from the center just like the first layer. But it may be that his info is out of date.
Well, there you go. Thanks, Ken. That's exactly the kind of first-hand empirical knowledge that's hard to come by in these forums.
Like a teacher of mine once said, "If your grandmother tells you she loves you, check it out!" I've learned a lot thanks to that advice. Of course, I also have a few things laying around the house that don't work anymore because I couldn't put them back together, but what the heck.
Or, in the immortal words of Tommy Boy:
"You know, you can get a good look at a butcher's ass by shoving your head up it but wouldn't you rather take his word for it?"