I’ve been a movie collector for close to thirty years, and have seen the evolution of the home theater hobby across multiple video formats. During that time, I have bought into every new state-of-the-art format as it came along, and regularly upgraded my favorite movies hoping to gain some measurable improvement in quality. As a self-professed videophile (hence the name of this site), I vowed never to regret chasing perfection. However, as I look at both the Blu-rays and the 4K Ultra HD discs in my collection, I find myself wondering if we may have finally hit the end of the line.

I suppose this post might have been titled “Is 4K Really Necessary?” That’s not a question I can answer, and I think asking it in that way unavoidably comes across as skeptical and pessimistic. The truth is that so-called “Ultra High-Def” 4K does (or can) have legitimate benefits over the regular HD video that has been the mainstay of the home theater world for the past couple decades. The other truth is that the closer to perfection we get, the more incremental the improvements become.

Let’s Get Physical

I’m a collector by nature. I like owning things that make me happy, and among those are movies. That’s one reason I continue to prefer physical media even as the market shifts toward digital streaming. I’ll watch a movie on streaming if I don’t already own a copy of it, or haven’t seen it before and am only looking for a rental or trial viewing. But for any movie I feel merits permanent ownership, I want to have it on disc. I find little appeal in digital purchases. It also helps that the video and audio quality are both usually better on disc than streaming due to less compression and bandwidth issues.

I’ve already written about my home theater journey from the Laserdisc days to present and won’t repeat that whole story here. I started collecting movies in the first place because LD was so much better than the lousy tape-based VHS format. DVD later improved upon that even further and introduced the mass public to the concept of home theater, yet the most important evolution in quality I’ve seen from this hobby was the jump from standard-definition to high-definition, especially the 1080p “Full HD” offered on Blu-ray.

Over the years, I’ve turned over my movie collection a few times – first from Laserdisc to DVD, then DVD to Blu-ray (with a quick stop at HD DVD and the occasional side trip to 3D). I’ve also found myself upgrading particular favorite titles multiple times over, even within each format, hunting for the best edition available at the time. A director’s cut, a fresh video remaster, an upgraded soundtrack, new bonus features, or even just special packaging (I can’t resist a good SteelBook) will often compel a new purchase from me, some of them imported from overseas.

Given that history, you’d think that I would also jump at the chance to upgrade as many of my Blu-rays to 4K Ultra HD as soon as they’re available. Indeed, I have complied by purchasing quite a few 4K Ultra HD discs. Still, UHD remains a relatively small percentage of my collection and I continue to buy new Blu-rays on a regular basis. I’ve allowed a number of titles that I could have bought in 4K to pass me by and am not always beholden to my instinct to upgrade, at least not to the degree I was when transitioning from DVD to Blu-ray.

Partly, this is due to my getting older and looking back at all the money I’ve wasted on so many discs that, to be completely honest, I’ve never gotten around to watching. At the same time, I must admit that, of the 4K discs I have bought, I’m not always convinced that the improvement they offer over the Blu-rays I already had was significant enough to justify another purchase, if I can see an improvement at all.

All About Those Ks

The UHD format promises twice the resolution over Blu-ray. In order to take advantage of that, the studios have had to create high-resolution 4K masters, often scanned from the Original Camera Negatives (when available) for older movies that predate digital filmmaking. When all the stars align with a high quality source and a good master, this can yield a 4K image with an appreciable increase in detail over 1080p Blu-ray.

The thing is, despite what the math may imply, doubling the resolution does not actually equate to an image twice as sharp in a literal sense. When comparing a Blu-ray and a UHD both transferred from the same 4K master source, the increase in visible detail is usually pretty small. The difference between 1080p and 4K is much more subtle than the difference between standard-def DVD and high-def Blu-ray. It’s better, yes, but it’s not hugely better.

Displayed at the same screen size, more pixels mean smaller pixels. At a certain point, some of the additional detail they carry may fall beyond human perception. Additionally, a great many movies simply don’t have 4K worth of detail to start. Numerous movies made in the digital filmmaking era (even those produced today) have either been photographed with 2K cameras or finished on 2K Digital Intermediates, and must be upconverted for release in 4K.

Older movies mastered from film sources have their own limitations. Depending on the film stocks and camera lenses used, most 35mm film productions topped out at somewhere less than 4K worth of detail on the Original Camera Negative (OCN). The release prints that actually played in theaters were several generations removed from that and were closer to the equivalent of 2K even in optimal screening conditions.

While a 4K disc derived from a 4K scan of the OCN can produce an image that looks better than the 35mm releases prints of the day ever did, in practice the higher resolution sometimes only serves to increase the visibility of film grain that would have been naturally masked or softened through the original dupe process, without much if any beneficial increase in relevant picture detail. On some UHDs I own, I feel like I can practically see down to the molecular level of the film element. This causes grain to look very coarse and sharply defined in ways it never would have appeared in theaters, and that the filmmakers probably didn’t intend. I’m not saying this is the case for every movie, but it’s true often enough that I don’t automatically trust 4K to be much of an improvement over 1080p.

Don’t Forget the HDR

Aside from the extra resolution, the other major innovations that 4K Ultra HD offers are High Dynamic Range and Wide Color Gamut encoding that regular Blu-ray can’t support, resulting in richer colors and a wider contrast range between dark parts of the image and peak highlights. In many cases where the difference between 1080p and 4K is imperceptible, HDR can be both a more prominent and more important benefit.

I feel that filmmakers and studio technicians are still trying to get a handle on these features, because results can vary wildly from title to title. Some content has very strong use of HDR, as if trying to show off what the format is capable of, while some is so restrained that it’s indistinguishable from Standard Dynamic Range (SDR). Between movies and modern TV shows, I’ve watched a lot of programs with “HDR” that never exceeds the capabilities of SDR, and some with HDR so aggressive as to be obnoxious.

This is especially a concern with older content. Technically, most 35mm film stock had wider latitude than SDR digital video, and a good HDR encoding can help to bring that out. However, the contrast range on film was not nearly so pronounced as is possible in digital Dolby Cinema, for example. Dialing up the HDR on an old movie can look unnatural. Even of modern digital movies, many filmmakers actually try to avoid an overly dynamic or vivid picture, as that can produce a “video” look that viewers find unappealing.

In both cases, some subtlety in the HDR grade is often more appropriate. Yet if the HDR is too subtle, viewers will wonder whether there was any point to using it at all.

Further complicating matters, not all 4K TVs and projectors display HDR equally well. HDR is much more difficult to calibrate than SDR, for those who bother to attempt calibration at all, and manufacturer presets are typically unreliable for accuracy. I’ve heard many viewers complain that HDR content is too dark on their screens, even to the point of being unwatchable compared to the brighter image they get from normal SDR. Issues like these can make 4K Ultra HD a tough sell.

The Upgrade Dilemma

Once Blu-ray (and its short-lived rival, HD DVD) hit the market, I was done with DVD right then and there. The rare few DVDs I’ve bought since 2006 have either been titles I felt would or could never be upgraded to HD, or discs that had some specific appeal as collectible items (i.e. fancy packaging and/or exclusive supplements). These days, I can barely tolerate watching standard-definition video and will avoid it if at all possible. 720p HD is the minimum standard I consider watchable in my home theater, and I only put up with that for cable TV series I have no way of accessing in better quality.

In my experience, 1080p HD represents a sweet spot that works extremely well for most home theater usage. When mastered properly, 1080p content (Blu-ray in particular, though streaming isn’t too far behind) can look terrific, with an impressively sharp and vibrant image even on a large projection screen. It may no longer always be the best of the best available, but I certainly don’t feel the need to toss out my movies on Blu-ray as soon as they become available on 4K UHD, the way I did when moving from DVD to Blu-ray.

4K HDR can and should look better than 1080p Blu-ray, but doesn’t always. Some discs are nearly indistinguishable, and some are decidedly worse due to poor HDR encoding, revisionist color grading, or other digital manipulations that attempt to change the look of a film rather than preserve it accurately. Make no mistake, those problems exist on Blu-ray as well, to an even greater degree, but the fact that it’s still happening with UHD leaves me wary of assuming that the new format will be better than the older one.

Where I find the most benefit upgrading from Blu-ray to UHD occurs when the older Blu-ray is known to be problematic, and a 4K release forces the studio to invest in a better video master. The 1987 action classic Predator, for example, was notorious for having a terrible Blu-ray release (called the Ultimate Hunter Edition) that smothered the entire movie in hideous Digital Noise Reduction in a misguided attempt to “fix” its grainy photography. The later 4K Ultra HD release undoes that mistake. That movie may never have had 4K worth of detail on its negative, and HDR does little for it either, but the simple act of not DNR’ing it to death makes the UHD vastly superior. Release on the 4K format is probably overkill for this title when a properly remastered Blu-ray likely would have been sufficient, but I’ll happily take the improvement where I find it.

On the other hand, any movie where I already own a Blu-ray edition that I consider to be very good to excellent quality is much less likely to inspire me to repurchase it in 4K just to get a small bump in detail or a light coating of HDR. I’ve done that for a few titles and mostly felt the effort and money were wasted.

Given the choice, I will default to buying a movie on 4K Ultra HD if any of the following criteria apply:

• I don’t already own a copy of the movie on Blu-ray.
• I own a Blu-ray edition known to be inadequate in some respect and the UHD is expected to be superior.
• It’s a newer movie photographed in digital 4K with an end-to-end 4K post-production workflow (including visual effects and the Digital Intermediate).
• The movie was photographed on large format film stock such as 65mm or IMAX.

Beyond those, I will evaluate each title on a case-by-case basis to decide whether I feel a 4K upgrade is necessary or worthwhile.

As always, I reserve the right to change my mind about any of these rules at any time, or simply be a hypocrite and ignore them when the mood strikes.