The lightsabers in Obi-Wan Kenobi looked a lot brighter than normal, and one technical issue may have made the footage almost impossible to fix.
Obi-Wan Kenobi made a change to the way Star Wars lightsaber scenes are made, and it may have rendered the footage unfixable. While many viewers noticed how much brighter the lightsabers were than in other live-action Star Wars projects, the technology used to create that effect may have backfired.
Star Wars movies under George Lucas shot their lightsaber fights with unlit stunt sabers. While the colored light blades were added in post-production, since the prop-sabers didn't naturally produce any light of their own, the lightsaber didn't provide any light onto the actors or surrounding the environment, other than a few circumstances where other on-set lights were used to simulate the effect. The sequel trilogy upgraded the process by creating more colorful lightsaber props with glowing tubes on set, creating a more interactive lighting effect.
Related: Was Obi-Wan Kenobi's Darth Vader Rematch Worth The Wait?
The Star Wars shows on Disney+ use a similar process to create the on-set lightsaber effect, although, in the case of Obi-Wan Kenobi, the bright blue of Obi-Wan's lightsaber didn't play nice with the camera technology, damaging the image in a way that might be irreversible.
Human eyes work by using "rods" to receive light and dark signals to aid vision in low light and peripheral vision, and red, green, and blue "cones" interpret the color from light reflecting off objects in the world around us. While full-spectrum light, such as light from the sun, appears white, it's comprised of various wavelengths across the full color spectrum. The vast majority of these wavelengths are invisible to the human eye (like infrared or ultraviolet light), but the wavelengths that are visible to the human eye are picked up by cones, 64% of which are dedicated to detecting red, 32% dedicated to detecting green, and only 2% dedicated to detecting blue. In a similar fashion, digital camera sensors detect light sensitivity, filtering light into red, green, and blue "RGB" channels for each pixel. The proportion of each RGB channel for a given pixel determines the color, while the overall level determines the brightness. They're designed to reproduce images the way human eyes see them, but they can still receive signals from outside the spectrum visible to humans, all of which is still measured with the same RGB system.
LED light technology has been around for a while, but only in recent years has it been used in photography because, although LED lights can combine red, green, and blue signals to simulate white light, it's not the same full-spectrum white light provided by other light sources. Human eyes can't always tell the difference between natural white light and simulated white light from LEDs, digital camera sensors can, which can result in some peculiar image behavior under certain conditions, especially with blue light spectrums, which camera sensors can be much more sensitive to than the human eye. Cameras, LEDs, and color management software have all evolved to improve our ability to collect and interpret RGB wavelengths, but it's still not a perfect science.
Under zero light conditions, when all RGB channels are at their minimum, digital camera sensors detect a black image, but as light increases, the camera sensors expose more image detail due to variations in brightness measured by the RGB channels until the light gets strong enough that it over-exposes and detail is reduced as the image becomes completely white when all RGB channels hit at their maximum capacity. When broad-spectrum light is filtered to a particular color, it still contains numerous frequencies measured at levels across all three RGB channels to maintain image detail, but when a camera captures light from colored LEDs (especially cheaper LEDs), the light contains much narrower color wavelengths than full spectrum light does, meaning it's far more saturated, causing groups of pixels to max out a given RGB channel resulting in a total loss of detail similar to overexposure, but instead of white, the blown-out area is fully saturated in the color of the blown-out channel. This phenomenon is known as chroma clipping.
Related: How Lightsabers Are Different In Original & Prequel Star Wars Trilogies
Chroma clipping can particularly be an issue with blue light. Blue LED light (particularly from cheaper LEDs) comprises a far narrower wavelength than already narrow red or green LEDs, so it has the potential to max out the blue RGB channel at lower brightness levels than other colors. Additionally, since blue cones only make up 2% of the color-receiving ability of the human eye, something illuminated with blue LED light might look fine to the naked eye when in reality it's being blasted with intense blue wavelengths we can't detect, but a camera sensor can. While "blue clipping" is similar in concept to an overexposure, it's not consistent with the way human eyes interpret light, making it appear very unnatural, especially on skin and faces.
One of the biggest technical differences between Obi-Wan Kenobi and the sequel trilogy is the sequel trilogy was mostly shot on film, which doesn't capture light the same way as a digital sensor, although there were also changes to the lightsaber technology making them brighter than any other live-action Star Wars project. Both the red and the blue lightsabers produce a level of saturation that results in a massive loss of detail when they glow on characters' faces. Additionally, the narrow spectrum colored LED light produces a densely saturated glow on the characters so thick it almost resembles a shadow more than an illuminating light as the white cores of the plasma blade added on top of the prop sabers in post-production, creating a sort of uncanny valley of light.
Based on the darker lighting conditions of the lightsaber duel scenes, it's possible the intention was to increase the brightness of the lightsaber props so they could function as the primary light source in the scene. The idea of an entire duel in the dark full of swirling red and blue blades casting shadows around the arena sounds like a really inventive and visually compelling idea, but without specially designed prop sabers with the kind of broad-spectrum LEDs that can be photographed at that brightness and serve as set lighting, the concept was doomed to produce unnatural light behavior and harsh color clipping.
Another potential consequence of the blue clipping is the muddier color grading of Obi-Wan's duels with Vader. While a dark scene lit primarily by lightsabers should normally have a higher contrast to improve visibility and accentuate the stylistic flair, the scenes in question weren't just dark, but seemingly had a lower contrast, resulting in generally dim, muddy lighting. When blue clipping is happening so prominently, especially on a character's face, the only way to really hide it is to keep brightness and peak light levels low. Even slight increases in brightness on many of the shots immediately reveal pools of 100% blue saturated pixels over the areas reflecting the most blue LED light.
Related: Why Does Obi-Wan Kenobi Look So Cheap
Flooding Ewan McGregor in highly saturated blue light isn't the best way to light the actor in the first place, but the harshness of the blue LED light is especially noticeable when compared to the much softer blue glow of the blue prop saber used by Daisy Ridley for Rey's lightsaber scenes in the sequel trilogy. The addition of interactive lightsaber lighting is one of the cooler things brought to Star Wars in the Disney era, but the dense saturation and blue clipping issues in Obi-Wan Kenobi show just how hard it can be introducing new technology to the filmmaking process, which hopefully illuminates just how incredibly George Lucas' visual and budget achievements were across his six Star Wars films.
While chroma clipping still happens from time to time, particularly on lower-budget movies or TV, a number of technology improvements make it easier to prevent and treat. LED technology is rapidly improving and a number of high-quality broad-spectrum LED lights have been designed specifically for photographic purposes, while many higher-end digital cameras calibrate their RGB levels to peak more naturally when one channel is maxed. The easiest way is to correct the issue during production by adding additional light spectrum, even just faint white light, to balance the channels better. Changing white balance or pushing each light color proportionally outside the desired range so it can be shot without issue and then adjusted back to the target colors in post-production is another possible solution, but the final product and the dim color grade to make it less noticeable suggests they weren't aware of the issue during the shoot.
Additionally, many higher-end cameras can collect broader RGB details, meaning the original raw footage is usable, but when footage is converted for streaming, it's compressed into a narrower range, which can force some colors to clip similarly to crushed black levels on compressed streaming video; however, circumstances such as the use of blue LEDs and the fact that such a prominent issue wasn't fixed before uploading to Disney+ suggest the blue clipping might be present in the raw footage, meaning it's possible there's not an easy fix short of digitally recreating the clipped image data and matching it to the lighting conditions.
The chroma clipping from lightsaber LEDs may not be the worst of Obi-Wan Kenobi's problems, but it is indicative of a level of technical failure that stands out for a franchise founded on low-budget filmmaking tricks. Many aspects of what makes Star Wars iconic are the result of creative solutions to technical deficiencies. In a recent interview with Collider, Ewan McGregor revealed that every line of dialogue in Star Wars: Attack of the Clones had to be redubbed with ADR because the movie was the first feature film shot with a digital camera, resulting in a number of unexpected combinations, such as the camera ruining all the on-set audio. While Attack of the Clones isn't exactly held up as the epitome of filmmaking, the fact that the dubbing isn't obvious is a testament to the magic of Lucas' post-production process and problem-solving ability.
Related: Obi-Wan Kenobi Is Missing Lucas' Secret Weapon
While it's unfortunate for such momentous scenes in the Star Wars saga to be marred by a technical issue like chroma clipping, hopefully, it results in Lucasfilm and Disney finding some creative solutions for future projects to push filmmaking technology forward. Who knows, with Ewan McGregor teasing the possibility of a second season, maybe Obi-Wan Kenobi will have another chance to deliver a properly lit nighttime lightsaber battle in the style of the duel they envisioned against Vader in the finale.
Related: Obi-Wan Kenobi Season 1 Ending Explained (In Detail)
Stephen has been writing for the site since 2016 and enjoys all manner of movies and TV, especially when it gives reason to obsess over minor irrelevant continuity minutiae. Stephen has been infatuated with movie magic on screen and off since wearing out his VHS copy of The Making of Star Wars when he was 7. This passion continues in his work as a film journalist, whether it's hunting down breadcrumbs about the Snyder Cut, breaking down box office trends, or obsessing over Rotten Tomatoes data, Stephen lives in the minutiae, as listeners of his podcast, Batman v Superman: By the Minute (with fellow-Screen Rant editor Andrew Dyce) know all too well. When he's not writing on the site, Stephen can be found obsessing over vintage camera lenses, chasing his tiny children around, or getting himself into trouble on Twitter @smcolbert. Yes, that's his real name.