Why Director Rian Johnson Dove into Camera App Development

In an age where smartphone photography grows more powerful by the day, one director known for Knives Out and Star Wars: The Last Jedi has chosen a path that seems to go against the grain: teaming up with an old tech-savvy friend to build a camera app that tries to give phone photos a cinematic quality. On The Vergecast podcast, Rian Johnson sat down with the host to explore the intersection of cameras, technology, and creativity, revealing the thinking behind an app called Chromograph.

From Film to Digital: A Director's Obsession with Images

Rian Johnson's camera history reads almost like a personal chronicle of technology. His primary shooting tool is a secondhand Leica M6 he picked up on eBay—bought while preparing for his third film, Looper, and used as a workhorse ever since, mainly for black-and-white film. On every shoot, he carries it around the set snapping candids, because "the process is so fast, you think the memory will last forever." The appeal of film is that you can't review it instantly—no one crowds around a screen; you just press the shutter and keep working.

His digital camera is a Leica M11, though he doesn't use it consistently. On the podcast he showed off an M11 centennial edition in black paint, joking that it was "the most random purchase ever," then immediately amending it to "maybe also the best." That obsession with camera craftsmanship runs through the entire conversation.

A Century-Long Truce Between Digital and Film

Johnson and his cinematographer Steve Yedlin have been friends since their college dorm days, and Yedlin has shot every one of his films. The two went through a long tug-of-war over film versus digital. Starting with Star Wars: The Last Jedi, they tried a hybrid of roughly 40% film and 60% digital, then gradually moved to all-digital. The reasons were partly technical—red-toned scenes are tricky on film, and VFX shots have to be digitized anyway—and partly practical: film equipment broke down more and more often, and film stock availability fluctuated.

What really won Johnson over was a line from Yedlin: "It's easier to make digital look like film than to make film look like film." Yedlin developed a custom LUT and grain-processing pipeline, and the final results forced even Johnson, a self-described film purist, to admit there was virtually no perceptible difference. Yedlin's view is that digital gives artists the greatest control over the image, and that the idea of "your style is determined by your medium" turns a creator into a consumer—someone just picking a preset product off the shelf.

Johnson wholeheartedly agrees, adding that film itself isn't some mystical magic. Kodak's color scientists spent decades iterating on film, boosting sensitivity and refining color rendition—that's continuous imaging science, not "magic in a bottle."

LUT (Look-Up Table) is a core tool in film and video color grading. Essentially it's a precomputed color mapping table: given an input RGB value, the LUT outputs a corresponding target RGB value. Colorists use LUTs to quickly convert footage from one color space to another or to apply a stylized "color recipe." The LUTs Yedlin developed for Johnson's films are precisely the key step that maps the linear RAW data captured by a digital sensor to a film-like color response. Unlike simple filters, LUTs are usually tied to specific exposure conditions and color spaces, so they need accompanying grain processing and tone curves to fully reproduce the film look. That's also why Chromograph has to shoot RAW and bypass Apple's default processing—only the raw data can correctly apply this cinematic-grade LUT.

Chromograph: Putting Cinematic Color Grading in Your Pocket

Chromograph was born out of a single reading session. After Johnson read a Verge article on how to take better photos with a phone, he started trying third-party camera apps to shoot RAW, but the workflow frustrated him: shoot in one app, import into another to edit, and RAW adjustments always felt like "getting lost in the woods without being able to explain how you got there."

So he went to Yedlin. Yedlin had already built him small tools that applied the image-processing pipeline used in his films to DNG stills. Johnson had long wanted to bring that pipeline to iPhone photos, but Yedlin initially brushed him off, saying "iPhone sensors are too noisy," and was eventually worn down by Johnson's persistent pestering.

Chromograph's core logic is straightforward: shoot RAW, bypass Apple's default image processing, and apply the color style Yedlin has developed for films over the years. That style evolves slightly from one film to the next, but the foundational LUT runs through all of Johnson's work.

The Design Philosophy of a "Convenience-Defying" Camera App

Interestingly, during development Johnson and his team repeatedly found their design decisions converging on Apple's own solutions. He admits that only when you actually build a camera interface from scratch do you realize how smart Apple's choices are around lens switching, zoom handling, HDR bracketing, and other details—"not the kind of design that looks cool, but design that's good in terms of usability, which is the real definition of good design."

But Chromograph also has things Apple doesn't. It includes a custom grain-size slider, whereas the iPhone's built-in "film mode" currently only toggles grain on or off, with a fixed and rather large grain size. Johnson likes to dial grain down to the minimum, citing his own deliberate overexposure experiment with T-Max 3200 film ("the largest grain known to man") to illustrate how subtle control over grain affects the look.

Another technical detail is bracketed exposure compositing. Apple's native multi-frame compositing is only available on Pro models, but Chromograph built its own version, so even non-Pro iPhones can capture multiple exposures at different settings and merge them to preserve highlight and shadow detail.

That said, Johnson points out a limitation: Apple currently doesn't allow third-party camera apps to use the 48-megapixel mode, capping output at 12 megapixels; only the native camera app's RAW mode can access full resolution. He hopes Apple will open up that capability to developers in the future.

The "Ceiling" of Smartphone Photography and How to Break Through It

Johnson admits that in the past, editing iPhone photos from the native camera with Snapseed could produce decent shots, but he always felt he'd hit a ceiling. For occasions that demanded serious photography, he'd bring a Leica M or a point-and-shoot. But after learning the RAW workflow and using Chromograph, he felt for the first time that "you can take genuinely good-enough digital photos with a phone"—professional shoots aside, of course.

One of his pain points was portrait halation. At a family gathering he shot a sunset RAW photo with Halide, imported it into Snapseed, and no matter how he adjusted it, it fell just short; but running it through Yedlin's pipeline, "all that harshness from direct light sources vanished instantly." That was what he calls his "epiphany moment."

Halation is an optical phenomenon from the film era: light passes through the emulsion layer, reflects off the back of the film base, and creates a red glow around high-contrast edges. When Yedlin was developing his digital film-emulation style, halation was one of the first elements he tuned. Johnson believes it's precisely this kind of very subtle thing that hugely influences how people perceive the difference between film and digital. He also mentions an interesting question Yedlin once raised: halation appears red on film because of the red layer on the back of the film base—so why not make it white or green in the digital age? That, precisely, is the freedom digital creation offers.

Halation is a typical optical artifact in film imaging. When strong light passes through the emulsion layer and reaches the back of the film base, some of it reflects back into the emulsion, creating a soft red halo around bright objects. The red color in color film comes from the anti-halation (AH) layer typically coated on the back of the base, which absorbs transmitted light but reflects red light. Digital sensors have no such physical structure, so native digital images produce virtually no halation. Yedlin deliberately rebuilt the halation effect when emulating the film look because it softens high-contrast edges and makes the image feel more "organic." The "harshness vanishing" that Johnson describes is exactly the digital halation simulation filling in that subtle but crucial perceptual cue.

A Complex Attitude Toward Technology and AI

A longtime tech enthusiast, Johnson has clear-eyed criticism of today's tech products. He says bluntly that AI being crammed into every personal device—"this garbage AI that nobody actually wants is making everything worse." He feels his excitement about "what the next generation of tech will bring" fading, and would rather go back to tinkering with film and old gear.

But he's no techno-pessimist. He was thrilled by the 3D-printed 6x17 large-format camera he brought along—designed and built by a friend, using an iPhone as a viewfinder, showing the possibilities of combining new manufacturing techniques with old photographic formats. He also showed off a friend's hand-built anamorphic lens in Leica M mount—"this is the first native M-mount anamorphic lens," Hoffman said with palpable admiration.

On HDR, Johnson is more vehement: "I hate HDR. I think it's a scourge." He feels HDR is eroding the theatrical projection and home-TV viewing experience—colorists spend enormous time carefully grading an image, and then a TV "cranks up the highlights" the moment you turn it on. He compares it to motion smoothing—"HDR, to me, is motion smoothing for color."

As for "what makes an image cinematic," Johnson declines to answer on Yedlin's behalf, but from his own understanding, he thinks the biggest factor is the curve—where the blacks are crushed, where the highlights roll off, and how the transition between them shapes the look. Next come grain and halation. He points out in particular that shooting RAW files and shooting film are highly consistent in logic: a film negative is itself a low-contrast, orange-masked "raw file," and its true "look" is created at the printing or scanning stage by choosing light and processing methods; the same is true of digital RAW files—it only becomes an image once you decide how to process it.

HDR (High Dynamic Range) in the consumer TV space usually refers to display standards like HDR10 and Dolby Vision that can render brighter highlights and deeper blacks. But what Johnson is criticizing is a different phenomenon: the "HDR enhancement" or "dynamic contrast" features that many TVs enable by default out of the box, which forcibly stretch highlights and boost saturation, undermining the colorist's original creative intent. This is similar to the controversy over motion smoothing, which uses frame interpolation to eliminate the judder of 24fps film but makes movies look like soap operas. Johnson calls HDR "motion smoothing for color," and the core issue is this: when a display device takes it upon itself to "optimize" the picture, the tonal curves that the director and colorist carefully constructed get overridden.

The Camera Renaissance and the Essence of Creation

Johnson observes that we're in the middle of a "camera renaissance." Young people are rediscovering CCD digital cameras because film became too expensive after it blew up around 2020. Apple added a film mode and grain simulation to new iPhones, and Google Pixel introduced a digital camera mode. But he hopes Apple will offer finer grain control rather than just an on/off switch.

He doesn't believe technology alone can replace story. Currently writing a new script, he says his next film may involve extensive "broad testing" to explore a visual direction different from the traditional film look of the Knives Out series. At the Nitrate Picture Show at the George Eastman Museum in Rochester, he saw vintage Technicolor prints and was deeply drawn to that "strange but beautiful" color rendering. But he's also wary of the danger of "focusing on the toys"—"it has to serve making the film look good, serve the story."

That may be precisely what's most interesting about Chromograph: it isn't a tool chasing spec-sheet dominance, but a director packaging years of accumulated imaging science into a shooting experience ordinary people can use casually. Johnson is clear: he made this app because "having a camera slung over your shoulder is annoying, carrying a backpack of four cameras is annoying, and I always have my phone with me." As the hardware ceiling of smartphone photography keeps getting pushed higher, creative control at the software layer becomes the next battleground.

CCD is a type of image sensor widely used in early digital cameras. Compared with today's mainstream CMOS sensors, CCDs typically have different noise characteristics and color response, and behave more "harshly" when highlights blow out. Young people's enthusiasm for CCD cameras in recent years is partly because their images carry a retro "imperfection" that contrasts with the heavily denoised, sharpened images produced by smartphone algorithms. Technicolor was the classic three-strip color printing process used in Hollywood in the first half of the 20th century, known for its extremely high saturation and distinctive color separation; its nitrate-base versions are now extremely rare. The vintage Technicolor prints Johnson saw at the George Eastman Museum are the visual legacy of a vanished chemical process, and they explain why that "strange but beautiful" color rendering sparked a new creative impulse in him.

One-line Summary

Director Rian Johnson and cinematographer Yedlin built Chromograph, bringing cinematic color grading to smartphone RAW photography.

Paragraph Summary

Rian Johnson and his go-to cinematographer Steve Yedlin co-developed the iPhone camera app Chromograph, whose core is shooting RAW photos, bypassing Apple's default processing, and applying the LUT and grain pipeline Yedlin developed for film. Johnson started out with a film Leica M6 and, persuaded by Yedlin that "digital makes it easier to control style than film," moved to digital. Chromograph includes a custom grain-size control and bracketed exposure compositing, giving even non-Pro models better dynamic range, though it's limited by Apple not opening up 48MP RAW access. Johnson criticizes AI bloat and HDR abuse for undermining creative intent, arguing that the essence of a cinematic look is curves, grain, and halation—and that the next battleground for smartphone photography is software control.