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Bekijk de volledige versie : Een genuanceerde visie op HD-dvd en BR



Pieter Kleine
03-04-2006, 22:55
http://www.audioreview.com/CESHDcrx.aspx

Sicco
04-04-2006, 07:52
hmm, vind het niet echt een bijzonder goed artikel eerlijk gezegd. staat, voor mij in ieder geval, geen nieuwe informatie in. zoals het artikel zegt en zoals eigenlijk overal gezegd wordt: het is afwachten wie de 'winnaar' wordt. daar hoef je geen genius voor te zijn om dat te bedenken :) ;)

Paul H.
05-04-2006, 09:27
Een beetje de algemene opinie die bij de meeste mensen nu geldt. Even afwachten en dan beslissen.

Edgar Smit
05-04-2006, 16:55
Ook hier op dvd.nl is er regelmatig nieuws geweest over HD-DVD en Blu-Ray (ik heb de berichten zelf geschreven) dus tot zover niets nieuws.

Zelf verwacht ik eigenlijk dat toch Blu-Ray als winnaar uit de bus zal komen, met name door de komst van HDMI aansluitingen die in de nabije toekomst ook ongecomprimeerd 5.1 (of meer) kunnen doorstromen. Blu-Ray heeft hierbij het voordeel van de grotere opslagcapaciteit per laag.
HD-DVD zal dus altijd meerlaags moeten worden om ongecomprimeerd beeld en geluid te kunnen weergeven, wat weer zal drukken op de productiekosten.

Echter, wanneer ongecomprimeerd geluid zal worden opgenomen is het nog maar afwachten of dat zoveel beter zal zijn DTS of DD (5.1 of hoger). Zolang dat verschil te verwaarlozen is, zal dat dus niet gebeuren en hebben beide kampen evenveel kans om deze herhaling van de BETAMAX-VHS oorlog te winnen.

IMHO dan.

Albert Kostwinder
09-05-2006, 14:31
HD-DVD: It's Here, and it's Spectacular
Evan Powell, April 21, 2006
ProjectorCentral.com

Tuesday, April 18, 2006, was official launch day in the USA for the new high definition DVD format known as HD-DVD, and the first HD-DVD player, the Toshiba HD-A1. I don't know how it went around the country, but here in Las Vegas most retailers weren't quite ready. Nevertheless, with a few phone calls we were able to track one down, along with three initial release discs—The Last Samurai, Serenity, and The Phantom of the Opera. We've been playing with it for the last few days, and I am happy to report our first experiences with it.

The Toshiba HD-A1 is currently retailing for a mere $499. HD-DVDs are selling at discounted prices as low as $18.99 through our Amazon-powered DVD store (click here for current and soon-to-be-released HD-DVD titles). For this modest investment you can literally transform the performance of your home theater. In fact, it is like upgrading to a higher resolution, higher performance projector for a fraction of the cost. (By the way, this article is not intended to be a formal product review of the HD-A1 as we still have some testing to do with it. Rather, this is a commentary on the HD-DVD format along with some first impressions of the HD-A1.)

I must admit to having been a bit skeptical of both HD-DVD and Blu-ray technology since the demos I've seen in stores and at trade shows have left me underwhelmed. Beyond that, there has been the preoccupation with whether HD-DVD or Blu-ray will win the format war. (Once it looked like Blu-ray had it locked up, but now all bets are off.) And then there has been the endless chatter about specs and outputs and whether you need a frightfully expensive 1080p resolution projector to get the real benefits from the new HD discs. All of this has contributed to a sense of confusion on the part of consumers as well as my own skepticism.

However, when the first images from the HD-A1 began to light up the screen Tuesday afternoon, all of my doubts melted away in short order. The image quality was superior to any of the previous demos I'd seen—pure, rock solid, pristine, razor sharp, highly detailed, and virtually artifact-free are just some of the superlatives that come to mind. It actually surpasses broadcast HDTV, for it is in the same class in terms of image resolution, but it is free of the noise and compression artifacts that are part of the broadcast signal. We have used several 720p resolution projectors for our initial look at HD-DVD and the results are beyond any expectation I had. Our associate Bill read my mind when he said "After seeing this it will be hard to look at standard DVD again."

In the last couple of days, several technical issues have been put to rest, at least for me. The first was the common accusation that the initial HD-DVD players like the Toshiba HD-A1 are deficient because they don't output "full 1080p" resolution, that they are "1080i only." I don't see this as a practical concern. All HD-DVD and Blu-ray discs will encode film-sourced material in full 1920x1080 progressive scan resolution at 24 frames per second, which is the film industry standard.

Unfortunately many folks are confusing 1080i acquisition with 1080i transmission. The primary reason we get interlacing artifacts in a 480i, 576i, or 1080i signal is that the frame was originally captured in interlaced format, with the odd scan lines and even scan lines being recorded at two different moments in time. When you reassemble two fields that are offset in time, you get jaggies, moire patterns, barber pole effects, and line twitter. That is not true of either HD-DVD or Blu-ray film transfers since the image is scanned progressively from a film frame that represents a single moment in time.

Therefore we would expect to see none of the common evidence of deinterlacing when watching HD-DVD or Blu-ray movies that are being transmitted via 1080i. Our first look at HD-DVD in 1080i confirms this expectation. After hours of viewing three different HD-DVD movies there is simply no evidence of any artifact that might be attributed to the fact that the signal was transmitted in 1080i format. The picture is as clean, stable, and as artifact-free as it could be. There is no visible defect in the image that would be eliminated by switching to 1080p transmission. (By the way, the fact that all three of these particular HD-DVDs are in the video codec VC-1 is another factor that contributes to the pristine image quality.)

Another pleasant surprise from our initial look at HD-DVD is that there is remarkably little motion judder being produced in the conversion from the 24 frame per second source to the 60 Hz display rate. I was expecting to see this and was looking carefully for it but simply could not see anything objectionable. Even more interesting was the fact that the Toshiba HD-A1 delivers better results with standard definition DVDs as well. We have several test scenes on DVD which judder and shimmy like crazy, and no reasonably priced DVD player or video processor has ever been able to handle them. But the HD-A1 significant reduced this annoying artifact and made these scenes much more watchable.

A big question on many folks' minds has been this: Since the signal is encoded in 1920x1080 format, don't you need to fork over the big bucks and get a 1920x1080 native resolution projector to get the best results? Absolutely not. The 1920x1080 encoding and transmission format is of great benefit to projectors in every resolution class. Meanwhile, native 1080p projectors and HDTVs are over-hyped and over-priced in today's market. Most of the reason for this is the subject of a different article, so let's stay focused on the central issue that relates to HD-DVD—do you sacrifice a lot of the medium's potential by playing it on a lower resolution projector, like the popular 720p models today?

Not at all. It is the amount of information in the signal, not the absolute number of pixels on the display, that has the most impact on an image's apparent resolution. If you don't believe me, just look at any of the entry level 854x480 projectors on the market today. These are built to map the 480-line signal of a standard NTSC DVD one-to-one onto the display matrix without vertical scaling. In theory this is the best resolution you can possibly get from a physical display that is 854x480 pixels. And these projectors usually generate amazingly good standard definition DVD video for their sub-$1,000 price tags. But what happens when you feed them HDTV 720p or 1080i signals? They are suddenly able to produce much higher resolution pictures that blow away the best standard definition DVD sources available.

How do they do this, you wonder? Don't they have to compress that big 720p or 1080i signal into 480 lines? Yes. Doesn't that mean that the 480-line physical display defines the limit of the projector's ability to define sharpness and detail? Sort of. Doesn't that mean that HDTV won't look any better than standard DVD on a little 480p projector? No, quite obviously not. HDTV always looks substantially better than standard DVD on a 480-line display. Image quality is not determined by the size of the pixel matrix as much as it is by the quality of the signal. Now, clearly the number of pixels on the display has some impact on image potential—we get more pristine HDTV images from 720p displays than we do from 480p displays. But signal quality always trumps display resolution when it comes to getting a great picture.

This same phenomenon is visible with HD-DVD and 720p projectors. Despite the fact that the physical pixel matrix is limited to 1280x720, by sending the projector a pure 1920x1080 signal it can deliver a picture that looks better than what you'd imagine you could get from a 720p display. In fact, from a normal viewing distance it looks almost as good as native 1080p. You can only begin to discern the difference from a close viewing distance, or with a very large projection screen.

So, do you need a native 1080p projector to get spectacular results from HD-DVD? Not at all. Could you even tell the difference between HD-DVD as displayed on a 720p projector vs. being displayed on a 1080p projector? From typical viewing distances the differences would be subtle to non-existent, but as you move closer to the screen or expand the size of the projected image to very large proportions, the advantages of a native 1080p resolution projector become more evident.

In short, laying out three to five times the amount of cash for a 1080p projector in order to get the maximum benefit from HD-DVD is unnecessary and ill-advised unless you have very large screen requirements. The price of 1080p projectors will come crashing down in the next two years, and most buyers will be much better served by buying a high performance 720p product today at a fraction of the price of the 1080p models, and then upgrading to 1080p down the line after prices have fallen to levels consistent with their incremental value.

Miscellaneous issues

Scaling. One of the common assumptions made about 720p projectors is that you get the best picture by having the video source (DVD player or video processor) rescale the signal to 1280x720 so it can be delivered to the projector in its native format. This does not hold true with HD-DVD as played on the HD-A1. Our testing so far has revealed that we typically get a sharper image by delivering all of the picture information on the disc to the projector via 1080i, and letting the projector rescale it to its native resolution. That may not always be the case if the projector has particularly poor scaling compared to that in the HD-A1, but so far we are getting the best results with 1080i transmission.

Motion blur. Back in the era when people first started making silent movies they wanted to expose just enough film to reasonably capture motion without wasting too much film. Initially, that exposure rate was 18 frames per second. However, when they wanted to go to talkies, they discovered that 18 fps was not fast enough to lay down a coherent audio track. So the speed was increased to 24 frames per second to accommodate audio, and the film industry has had 24 fps as a standard since the 1930's. As everyone who has been to the movies knows, 24 fps is not fast enough to resolve rapid motion without some blurring effects.

HD-DVD and Blu-ray will carry this blurring-of-motion tradition forward to some degree since it is a limitation of the original film source. It makes perfect sense that film transfers will be 24 fps on both HD-DVD and Blu-ray since that is what the film source is. However, users should not expect that 1920x1080 super high resolution will make the blur go away.

New technology: The HD-A1 is a new type of disc player that is designed to process data at much faster rates and in a wider variety of formats than a conventional DVD player. Accordingly it does not respond as quickly as a standard DVD player. It takes more time to boot up, and more time to evaluate and recognize the type and format of disc it has been given. Expect it to behave a little more like a computer and a little less like a conventional DVD player, and you will save yourself some unnecessary frustration.

Also, we have been testing the HD-A1 with a variety of projectors to ensure that it synchs up on HDMI, does the HDCP handshake, and that the projector is able to recognize and display the signal. In the good news column, we have tested the Sanyo PLV-Z3 and PLV-Z4, the Panasonic AE700 and AE900, the Epson Cinema 800, the InFocus Play Big IN76, and the Dell 5100MP, all without any problem at all.

In testing the Viewsonic Cine1000 and projectiondesign evo2sx+, we got a mixed result—these projectors would play the movie with no problem, but could not see the menu system on the player. This needs to get squared away as it really helps to be able to see the HD-A1's set up menu.

The most serious problems we've seen are with Optoma models. The HD7100 occasionally synchs with the HD-A1's HDMI output, and when it plays it works beautifully. But sometimes the HD-A1 and the HD7100 are unable to make a connection and the HD-A1 reports an HDMI error. The EP910 initially synched up with the HD-A1, but then froze up with the remote and onboard control panel becoming inoperable. A hard shutdown was required to get it back in operation. Finally, the HD72, which is one of the hottest 720p home theater projectors on the market at the moment, was unable to facilitate a connection to the HD-A1 via the HDMI port. In every attempt to get them to lock, the HD-A1 reported an HDMI error.

[EDIT UPDATE: Further testing of the Optoma HD72 reveals that once the HDMI Error appears in the player's display, if one clicks the PLAY button on the player's remote quickly three times, the condition is overridden, the connection is made, and the movie plays with no further difficulty.

In general, after further evaluation over the weekend, the compatibility issues noted appear not to be related to Optoma models specifically, but to all models we have tested which use a DVI (HDCP) port instead of an HDMI port. We will continue to research this and report as new information is available. EP 4/24/06]

As noted above, this is not a full HD-A1 product review. We have been testing video performance of the HD-A1 on a variety of digital projectors that we have on hand without bothering to exercise all of the features of the HD-A1. All of the basic DVD player features such as freeze frame, slow motion, fast foward and reverse, forward and reverse skipping to chapter breaks are working fine. However we have not done any testing of the advanced features or the audio output options.

HD-DVD or Blu-ray?

There is no need to rehash every argument in favor of one format over the other here. There is no way to predict which format will win, or even if there will be a winner. In fact, there is no reason why these two formats cannot live and compete in the same market space. Movie studios had no trouble releasing their movies to DVD in both widescreen and full screen editions so consumers could get them in the format they preferred. Similarly, many studios are now indicating they will release their films in both HD-DVD and Blu-ray format. If a significant installed base of both types of players develops, the rest of the studios now committed to one or the other will eventually follow suit. After all, their business is selling movies, not hardware.

HD-DVD clearly has a price advantage as far as the disc players are concerned, at least at the present time. Toshiba's HD-A1 is $499, while the Samsung and Sony Blu-ray players scheduled for release this summer are being quoted at $999. HD-DVD also has a time-to-market advantage—it's here and you can get players and discs today, while you'll still have to wait several months for Blu-ray players to hit the market. For some reason, despite the delay in Blu-ray player availability, Sony still plans to release several Blu-ray DVD titles on May 23. I suppose one could use these discs as portable make-up mirrors until the Blu-ray players begin to show up in (hopefully) July. But there won't be much else you can do with them. Nevertheless, for those who want to start collecting early, you can pre-order Blu-ray DVDs from Amazon through our DVD Store.

Blu-ray has greater storage capacity and faster data transfer rates, and for certain applications this is an obvious advantage. But the vast majority of movies will fit on a single disc in 1080p/24 resolution in either format, and HD-DVD transfer rates are ample to drive high resolution movies. So home theater enthusiasts interested in 1080p movies won't even know or care about maximum capacity and transfer rates.

Then there is the "1080i vs. 1080p" issue. But after having seen the results of the HD-A1's 1080i output on several projectors, it is clear that in practical terms 1080p transmission will be of marginal relevance to the large majority of users. All 1080 lines of picture information on the disc get to the projector either way with no interlacing artifacts, and image quality on 720p projectors will match or exceed anything you've ever seen before. There just isn't much potential to get any better, and further improvements will be subtle at best.

In summary, the Toshiba HD-A1 simply produces a magnificent image with HD-DVD discs. Never before has the consumer been able to take his or her home theater to a whole new level of mind-blowing performance for a mere $500. I have no idea how the HD-DVD vs. Blu-ray battle war will play out, and there are yet many battles to be fought. However, based on what I've seen this week, if HD-DVD wins it's okay by me.

As of this writing, if you want to pick up a Toshiba HD-A1 you'll probably be standing in line. Most resellers sold out quickly, and many units were pre-sold. Toshiba tells us they are rushing to air-ship more inventory into the country, and they expect to have 3,000 dealers and retailers restocked by the end of next week.

Voor iedereen die nog steeds denkt dat je alleen met een 1080p scherm mooi hd krijgt... :wink: