After months of teasing Game of Thrones recently aired what purportedly was the biggest and longest battle sequence in film history. But as soon as the episode aired the internet started to echo with criticism the battle was too dark and incoherent. While the makers adamantly claim the visual darkness in the episode was an intentional creative choice an enormous volume of fans are upset they couldn't properly see what was going on.

So what went wrong? Did the creators of the show genuinely make an unprecedented mistake, underlighting the entire episode? Or did modern streaming technology, and old television sets, turn a gorgeously dark and tense battle into a murky, gray jumble?

"Everything we wanted people to see is there"

It's not hyperbolic to suggest that The Long Night was one of the most highly anticipated television events of the last decade. The episode was the culmination of years of Game of Thrones plotlines, all reaching a crescendo in a massive battle between a zombie army and a disparate coalition of humans.

The Long Night was always going to be a dark episode, both figuratively and literally. The entire show's catchcry of "Winter is coming" was fulfilled in one long, dark, harrowing battle. Winter is here and the army of the dead were bringing literal darkness to the world of Westeros.

Fabian Wagner, the cinematographer behind the episode, has been stridently defending his work in the days since it aired. Wagner suggests the episode was designed to be dark but he definitively notes, "Everything we wanted people to see is there."

Wagner's statements imply a certain degree of chaotic incoherence was built into the aesthetic of the episode. There are undeniable stretches of battle where the viewer is not meant to clearly see what is going on. This aesthetic mode has been dubbed "chaos cinema" by some film theorists, a type of modern action filmmaking where clear visual coherence is sublimated to a kind of frantic sensory overload designed to convey a feeling of overwhelming intensity.

When chaos cinema works it can result in truly thrilling and visceral experiences, but when it doesn't work it can leave one feeling frustrated and confused by the relentless confetti-like visual mess unfolding on screen. Considering how loud and vociferous the response has been against this recent Game of Thrones episode it is fair to say something went drastically wrong.

But did the makers of the show simply underestimate the general public's tolerance for 80 minutes of harrowing chaos cinema? Or did the transmission of the episode shine a light, so to speak, on a fundamental shortcoming in our current broadcasting and streaming technologies?

HBO claims there were no errors and the episode was broadcast as intended HBO

It's not you ... it's the stream

In one of his defensive interviews, Wagner claims one of the problems could be viewers simply watching the episode on badly calibrated television sets in brightly-lit rooms. "A lot of the problem is that a lot of people don't know how to tune their TVs properly," Wagner says.

And to a degree he certainly could be correct. The show is undoubtedly edited and mastered using top of the line visual sources, possibly OLED screens. So the richly conceived black visuals the creators observed in post-production on the episode may have turned into muddy grays for audiences with older television sets built on other display technologies, such as LCD.

However, a much larger concern hovers over the episode, potentially explaining why even a home viewer with a new, perfectly calibrated OLED TV could still have a frustratingly incoherent experience, and it all comes down to the limits of video compression technology and how the show is delivered to most households.

All television transmissions are compressed to some degree, whether you are watching cable, satellite or streaming off the internet. Many modern film and television productions are filmed using 8K cameras, and subsequent post-production is usually completed using extraordinarily high definition footage. At the point a final master file is rendered some compression will inevitably be applied, depending on what the final exhibition format is.

Many standard 2K DCP files that play in cinemas still ultimately take up around 150 gigabytes of data for a 90 minute film. Even this is compressed from the original post-production file that potentially was well over a terabyte. But, when dealing with the world of streaming television we rely on even heavier compression. After all, there aren't many people who could effectively stream a gigabyte a minute without constant buffering.

For the most part, streaming compression technology works very well. That latest stunning David Attenborough nature documentary on Netflix looks wonderful, and is probably crunched down to, at most, a few gigabytes for an hour episode. One of the bigger challenges that compression technologies haven't been able to decently resolve is accurately encoding dark or dimly-lit images. Subtle changes in color tone comprise a great deal of image data, and the more an image is compressed, the more those nuanced gradients get mashed out resulting in an artifact often referred to as color banding.

A simple example illustrating the concept of color banding Public Domain

The Long Night presented a perfect storm of all the visual aspects least suited to compression. When a grayish blue fog swirls across the dark battlefield the picture simply turns into an incoherent two-tone mess. Uncompressed, in a post-production suite, this quite possibly was an incredibly evocative and beautiful image, but to most viewers on a Sunday night watching from home it was incomprehensible.

No one saw this coming

In a statement, HBO claims there were no issues across any of its platforms. This implies the show was broadcast and streamed without any problems or compromises. In a comment to Motherboard James Willcox, from Consumer Reports, seems to strongly disagree. Willcox notes the problem was worse with internet streaming of the episode, but still apparent through cable and satellite platforms. It is suggested that possibly the fundamental problem was created at the point where the show was being encoded or compressed.

"So either HBO is screwing up the encoding of the show, or there's not sufficient bandwidth to transmit the show without losing the bit detail in darker images," Willcox said to Motherboard. "You don't really notice it as much in brighter scenes. I was able to watch it on an OLED TV, which does a better job with blacks, and even on these sets the issue remains. It's not the TV technology."

The cinematographer behind the episode is adamant he shot things correctly with enough light HBO

It's a startlingly novel technological challenge, and it seems no one saw it coming. The makers of Game of Thrones certainly made a bold creative choice in shooting this huge battle in the dark, and there is no way the episode would have gone to air if the creative team was not happy. But, due to the unexpected limitations of our current broadcasting and streaming technologies the episode has ultimately left a multitude of fans frustrated and unsatisfied. Fans will now await the blu-ray release in the hopes of finally watching this fascinating episode of television closer to how it was meant to be seen. Guess there may be some life still left in physical media.