HD Advisor 52 Pick-Up

Posted Fri Apr 2, 2010 at 11:45 AM PDT by

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Answers by Joshua Zyber

'Avatar' Aspect Ratio Controversy

Q: Is there going to be any way to use the 1.78:1 'Avatar' Blu-ray on Constant Height systems? If the aspect ratio is 1.78:1 "open-matte / full-frame," is there any way to first crop it to 2.35:1 before stretching it in the projector to use with an anamorphic lens? Or are we just going to have to zoom it if we want 2.35:1?

I saw the film six times in digital 3-D at 2.35:1. It looked great and the 3-D was pretty dang immersive. I did see it once in IMAX. While the extra top and bottom was enveloping, I preferred the 2.35:1 to the over-abundance of headroom in IMAX. The compositions seemed overly "open" to me. I am politely dubious about any director changing his mind about his OAR after he shoots the film, and it is pretty obvious from how well Cameron composed the 2.35:1 that it was his initial intent. Has Cameron inadvertently set back the cause of 2.35:1 OAR for home theatre? I will bet actual money that studios and the "Fill my screen!" contingent will be citing Cameron's AR decision for years to come. I hope Cameron hasn't made 1.78 the new Pan & Scan.

A: Much like 'The Dark Knight' on Blu-ray, 'Avatar' will pose a conundrum for home theater viewers with 2.35:1 Constant Image Height projection screens. The movie was shot with digital cameras at a native aspect ratio of 1.78:1. When it was released theatrically, all 2-D prints of the movie were matted to the "scope" 2.35:1 ratio. (Similar to how the Super 35 film format is used.) On the other hand, IMAX 3-D prints were presented at an open-matte 1.85:1 with additional picture at the top and bottom of the frame. Meanwhile, digital 3-D theaters were distributed copies of the movie in both aspect ratios, and were instructed to project whichever would be larger on their screens.

In interviews conducted last year, James Cameron stated that 1.85:1 was his preferred aspect ratio for the 3-D version of the movie, because he felt that the extra height made the 3-D effect more immersive. However, at the same time he also emphasized, "But only in 3-D. I still like the scope ratio compositionally for flat projection." Because of this, it was expected that the initial 2-D Blu-ray release of 'Avatar' would be presented at 2.35:1, while an eventual 3-D Blu-ray down the road might be opened up to 1.85:1.

In recent events, Cameron has turned around on this issue. The first Blu-ray release, although still just 2-D, will be presented in a fully open-matte 16:9 (1.78:1) transfer. According to Cameron, "Even though I love the Cinemascope ratio compositionally, I actually found myself falling in love with the movie in 16:9, as we went along, and I prefer to watch it in that."

Personally, I have mixed feelings about this. Although I support the right of a director to control the ideal presentation of his movie, I'm not much of a fan of filmmakers who impose revisionist changes to their movies after-the-fact. I saw 'Avatar' theatrically at 2.35:1, and the framing looked very well composed to my eye. While I haven't yet seen the 'Avatar' Blu-ray, I fear that the 16:9 ratio may look too loose and awkward with the additional headroom and footroom. (Much as most open-matte transfers of 2.35:1 movies look when broadcast on networks such as HBO-HD.) I did not see the movie in IMAX or any other 1.85:1 screening. (Once was enough for me.) At the present time, I'll have to reserve judgment until I can get the disc in my hands.

As far as the Blu-ray goes, CIH viewers will have two options. They can watch the movie at the director-sanctioned 16:9 with pillarboxing on the sides (as they would watch any other non-scope movie). Or they can zoom the movie to fill the 2.35:1 screen, cropping picture off the top and bottom. The latter option will really only work for those viewers who use electronic scaling and anamorphic lenses for CIH, or otherwise have some form of electronic blanking (such as from a video processor) to achieve the 2.35:1 ratio. Those who use the "Zoom Method" without blanking will find parts of the picture projected above and below their screens. Under normal circumstances, black letterbox bars are not noticeable when projected in this manner. However, active picture in that area will likely be distracting.

Even so, attempts to crop or mask the picture assume that the 2.35:1 portion of the movie was extracted from the direct center of the 16:9 camera image. That may or may not necessarily be the case. If the 2.35:1 extract was taken above center or adjusted on a shot-by-shot basis, cropping or masking the Blu-ray from the image center will look incorrect, and will not truly represent the "scope" theatrical presentation. Again, I'll have to wait for the disc to arrive before I can verify that.

As for your question about whether this 'Avatar' Blu-ray will usher in a new era of 16:9 Pan & Scan, in which studios crop and mangle 2.35:1 movies to fill viewers' screens, I doubt that any one movie will have that sort of impact. The concept of Original Aspect Ratio has been well established and respected on the format to date. This is clearly a case where the director has control over the final product, and simply decided that he wanted to change it for home video.

Then again, what do I know? I predicted that 'Avatar' was doomed to box office failure. I had absolutely no idea that audiences would be so enamored with Smurfy blue Indians riding dragons in a magical rainforest. I sure wasn't. C'est la vie.

Blu-ray vs. Film vs. IMAX

Q: I've always been told that Blu-ray at 1080p has less resolution than 35mm film. I understand that the two don't directly compare, since one is analog and the other digital. The point being that there's still room to improve in resolving film. On the other hand, in discs like 'The Dark Knight', there's a noticeable increase in clarity during the scenes filmed on IMAX stock versus those shot on standard 35mm film, even though both are being watched from the same Blu-ray disc and shown on the same screen.

Common sense would tell me that if Blu-ray is maxed out before even getting to 35mm resolution, then there shouldn't be a visible gain when introducing an even higher resolution product such as IMAX. The extra clarity/resolution would be lost in compression to 1080p. Pretend Blu-ray is an empty one-gallon jug of milk, 35mm film is 2 gallons and IMAX is 4 gallons. If you try to pour in your IMAX to the Blu-ray jug, you're still only going to be able to hold 1 gallon – just the same as if you poured in the 35mm film. Both have extra resolution that is wasted.

A: It's generally accepted that 35mm film has more potential resolution than Blu-ray or high definition video. Just how much of that potential actually makes it into the final product depends on a number of factors. The film stock and lighting conditions used in the production, choice of camera filters, and other stylistic decisions may result in a photographed image that doesn't exhibit much more detail than HD video is capable of resolving, and sometimes (perhaps often) less.

IMAX 15/70 film stock has almost ten times more negative area than 35mm, and correspondingly can capture much more detail. Although technically both IMAX and 35mm must be downconverted to HD resolution during a Blu-ray transfer, the higher quality source will ensure that more of that detail carries through the downconversion process. Even on DVD, IMAX movies typically look better than 35mm movies, because they were better to start.

In the specific case of 'The Dark Knight', the entire Blu-ray was mastered from an IMAX source. While that means that the scenes photographed on IMAX stock come direct from the high-quality IMAX 15/70 film elements, it also means that the 35mm portions of the movie had been filtered through the IMAX DMR upconversion process prior to their Blu-ray downconversion. In addition to being needlessly scaled twice, the DMR process adds both Digital Noise Reduction and artificial sharpening to the image. As I've written previously, I am no fan of what IMAX DMR does to a 35mm film. Ultimately, 'The Dark Knight' Blu-ray does not represent the best that the 35mm sections of the movie (the vast majority) could have looked if transferred direct from 35mm without any of the IMAX DMR mucking around.

Scaling and Native Resolution

Q: My question is about resolution settings on an HTPC while watching Blu-rays, and how it relates to interlaced/progressive output. I'm trying to decide which resolution has a better picture in the end. I realize progressive scan output is superior to interlaced in general, but my TV only supports 720p or 1080i. With an HTPC, I can select any resolution I wish, but I'm not sure which is better. I basically have 3 options: the TV's native resolution (which I can’t remember offhand, but is close to 720p), 1280x720 (720p), or 1920x1080. Which resolution is likely to output the best picture? I realize in general, native resolution is usually best for a PC, but then I'm getting 720 instead of 1080 while watching a Blu-ray, correct?

A: A digital TV has one and only one native resolution. All content input into the TV will be displayed at that native resolution, regardless of any additional scaling you may have done earlier in the signal chain. The TV itself will perform final scaling just prior to the image hitting the screen. If your TV's native resolution is "close to" but not exactly 720p, I'm going to guess that it may be 1366x768 or something similar. You should check your owner's manual or search online for this information about the model number. For the purposes of this explanation, I'll use 1366x768 in the example.

Ideally, if the video content you're watching is not natively the same resolution as the TV screen, you only want to scale it once. For example, a Blu-ray scaled from its encoded 1920x1080 resolution directly to 1366x768 by your HTPC should produce the best results. Choosing any other resolution will cause the image to be scaled twice, once by your HTPC and then again by the TV. Double-scaling increases the likelihood of mathematical errors in the scaling process, which may result in visible softening or pixelation artifacts.

Unfortunately, not all HDTVs can accept input signals with their native resolutions. Many models are programmed only to accept the standard 720p or 1080i formats. In this case, 720p is closer to the native resolution of the TV, but 1080i is closer to the native resolution of the content on the disc. Your results will depend on the specific deinterlacing and scaling capabilities of both your HTPC and your TV. You may have to try it both ways to see if there is any discernable difference.

If the TV can accept a native resolution signal, that's probably your best bet. No matter what you do, you'll never get a true 1080p picture on your current screen, because the screen isn't capable of it. So you shouldn't worry too much about the Blu-ray output being less than 1920x1080 if the TV is going to scale it down from that anyway.

Homework Assignment: You Be the Advisor

The HD Advisor knows many things, but he doesn't know everything. Some questions are best answered with a consensus of opinions from our readers. If you can help to answer the following question, please post your response in our forum thread linked at the end of this article. Your advice and opinions matter too!

PS3 Playback Problems

Q: DVDs play back fine on my PS3. However, SD content on Blu-ray discs causes the PS3 to stop all video from working until I do a "hard restart" of the whole system. I have to hold the power button down until the PS3 powers off and then reboots. I then have to re-enter all of my settings and preferences from scratch. This means that I cannot watch special features on some of my discs. This might be a common problem that people think is the "green screen of death," but really not. I'm glad I was able to find that restart thing online. In case it matters, my components are the 80GB PS3, Onkyo TX-SR705, and Mitsubishi WD-73737. All are connected via HDMI.

JZ: I have a PS3, but honestly don't use it enough to have experienced this problem. Have any of our readers had this issue?

Check back soon for another round of answers. Keep those questions coming.

Joshua Zyber's opinions are his own and do not necessarily reflect those of this site, its owners or employees.

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