HD Advisor 17

Posted Fri Jun 12, 2009 at 12:00 PM PDT by

Editor's Note: Each Friday, High-Def Digest's own HD Advisor will answer a new round of questions from our readers. If you have home theater questions you need answered, send an email to [email protected]

If you've already sent a question and don't see it answered yet, please be patient as we work our way through them. To browse through previously answered questions, visit the main HD Advisor page.

Answers by Joshua Zyber

Digitally Photographed Movies

Q: My question is regarding movies shot digitally, such as 'The Curious Case of Benjamin Button' and 'Cloverfield'. Correct me if I'm wrong, but since these movies were primarily filmed using digital video cameras, isn't their maximum resolution rather limited compared to movies shot on film? They may look spectacular now but in 20 years when we have Ultra Supreme High Def (or whatever we'll call it), won't they look crappy because of the limitations of digital cameras while an oldie like 'Casablanca' will look even better?

A: In essence, you're correct. Movies photographed with digital cameras are forever locked into the resolution at which they were shot. Both of the movies you cite were similarly photographed with a mixture of Sony CineAlta F23 and Thomson Viper FilmStream cameras. As a result, they both have native resolutions of 1080p (or close to it, depending on the specific variables of each production). So, as you can see, they're both more or less at the same resolution as Blu-ray.

With that said, digital cinematography has greater color depth and less video compression. The native format of these movies is still superior to Blu-ray in some respects. However, the crux of your point has merit. If the home theater industry were ever to move to a higher-resolution video standard (e.g. 4k), 1080p movies like these would need to be upconverted to that resolution, and would look inferior to newer content shot natively at the higher resolution. Or to 35mm film content scanned at that higher resolution.

Likewise, this limitation also affects many modern movies shot on 35mm film. These days, a Digital Intermediate stage during post production is often used for color correction, visual effects, and whatnot. The movie is digitally scanned, adjusted, and then output back onto film. Sad to say, this DI stage is usually done at 2k resolution, which is very close to 1080p. So, even though the new 'Star Trek' was shot on 35mm, it's forever locked to 2k because that was the resolution of its DI.

On the other hand, film is an analog photochemical medium. Its native resolution cannot be directly expressed in terms of pixels. There has been much debate about exactly what resolution 35mm film would equate to. Depending on whom you believe, a 35mm movie is comparable to anywhere from 4k to 25k. Much of the confusion stems from the difference between 35mm still photos and projected motion pictures, which cannot be measured the same way as one another. Factors such as film stock, lens choice, lighting, and exposure levels will also affect the apparent resolution of any given movie. I'm not going to pretend to know the correct answer to this, but I have a feeling that it's closer to the low end of that range.

In any case, it's safe to say that 35mm film has a theoretical resolution much higher than our current 1080p home theater standard. So long as a movie didn't have a Digital Intermediate that locks it into a specific resolution, it can be rescanned in the future for a higher-resolution transfer. In that case, yes, an old movie like 'Casablanca' has the potential to look a lot better than a newer movie like 'Benjamin Button' on the next generation of home video formats.

DVD Upconversion

Q: From what I hear, the Oppo BDP-83 is supposed to be top-notch in terms of its upconversion capabilities. However, I have a 40-inch LCD display and I'm not sure I'd notice the difference between, say the BDP-83 and Oppo's own DV-980H. It's DVD only as you know, but also highly praised for its upconversion and considerably cheaper. Is there a minimum screen size at which the higher-end upconverters tend to be effective over and above cheaper alternatives?

A: As I'm sure you know, DVD video is encoded at 480i resolution. In order to upconvert this to a higher resolution, that interlaced 480i signal must first be deinterlaced to progressive 480p frames, and then those frames will be scaled to your desired resolution. The scaling process is always based on whole frames, not on interlaced fields.

If we're strictly looking at the DVD upconversion side of things (I'll assume that you get Blu-ray playback from another component), the primary difference between the two models you cite is that the BDP-83 has superior deinterlacing to the DV-980H. Deinterlacing is a very critical step. If not performed correctly, you'll get combing artifacts and jaggies in your video image, either of which will be perfectly visible on a 40" screen.

That's not to say that the DV-980H has bad deinterlacing. When comparing well-authored DVDs transferred from film-based movies with a steady 3:2 cadence, I doubt you'll see much difference between these two players. That type of content is pretty straightforward to deinterlace. However, video-based programming or material with complex mixed cadences can be a much more difficult challenge. Anime content in particular can often be a deinterlacing nightmare.

You'll need to take your own viewing habits into consideration when making this decision. If you exclusively watch big-budget Hollywood movies from the major studios, either one of these players will probably suit your needs just fine. But if you watch a lot of anime, concert videos, documentaries, and other eclectic content, quality deinterlacing will make a lot of difference.

The BDP-83 has essentially been built off the design of Oppo's previous top-end model, the DV-983H (now discontinued), with the new addition of Blu-ray functionality. It uses an Anchor Bay deinterlacing chip that is one of the best in the field for just about any type of content you can throw at it. On top of all that, it's also a great Blu-ray player. If you're looking for an all-in-one solution, it's worth serious consideration.

RS-232 Interface

Q: Despite my strong recommendation that the new projector my company just purchased should have an HDMI port, they decided that the manufacturer's stated contrast ratio was the most important factor. Pioneer will offer a professional level Blu-ray player this fall that supports RS-232, which begs the question: will RS-232 provide the same quality picture that an HDMI connection would? Is it as good as Component, even?

A: In home theater gear, the RS-232 port is generally used for automation purposes (for example, turning on a string of equipment in sequence and adjusting each to the proper settings automatically). It is not used for transmitting video. For that, you will still need to use the Blu-ray player's HDMI or Component video outputs.

If the projector your company bought lacks an HDMI connection, you'll need to use the Component inputs instead, assuming it has some. If that's not the case either, then it most likely will have a VGA input. In that scenario, you'll need to run the Blu-ray player's Component outputs through a Component-to-VGA Converter. Please note, a simple adaptor cable will most likely not work here. A Blu-ray player's Component connection outputs video in YPbPr format. Unless specified otherwise, the projector will almost certainly be expecting an RGB signal over its VGA input. Therefore, you'll need a Converter that can transcode the signal from YPbPr to RGB. This will be more expensive than a basic adaptor cable.

One more note: Because a Blu-ray player's HDMI output is encrypted with HDCP, you also cannot use an HDMI-to-VGA adaptor or converter. The HDCP encryption will prevent the signal from being transmitted. You'll need to stick to Component.

Homework Assignment: You Be the Advisor

Some questions that the HD Advisor receives 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!

Budget A/V Receiver Recommendations

Q: You mentioned previously that the PS3 can only internally decode Dolby TrueHD and DTS-HD Master Audio and send them out as PCM. The only Blu-ray player I use is a PS3. It's just too hard to find "Linear PCM" in the features listing on any web site. Are there any cheaper receivers that can accept uncompressed PCM at these bit-rates without having built-in decoders for the other two codecs?

Check back next week 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.

See what people are saying about this story in our forums area, or check out other recent discussions.

Tags: Joshua Zyber, HD Advisor (all tags)