Rear diopters create a vintage canvas for ARRI Signature Prime lenses on Pepsi commercial

From the Oscar-nominated hit “1917” to the upcoming Marvel blockbuster “the Eternals,” the ARRI Signature Primes have established themselves as one of the hottest lens series, spanning genres such as feature film production, corporate, music videos, natural history, and commercial television to name a few. Creatives have been drawn to how the lenses render warm, natural skin tones alongside open shadows with crisp blacks. 

Less known is the ability to customize the look of the Signature Primes through the rear magnetic filter holder. Each lens in the Signature family is equipped with this creative flexibility. The rear filter allows cinematographers to easily add rear nets, diopters, and other materials to customize the look of the lens without permanently altering the lens or exposing the lens components on set, which may result in contamination. The use of rear nets and diopters dates to the early days of filmmaking. Cinematographers would apply fabrics, like pantyhose, across a lens to create a softer, diffused look. These retro filmmaking techniques are still used. 

“ARRI is first and foremost a filmmaking company,” says Art Adams, ARRI’s Cinema Lens Specialist. “When we made these very sophisticated lenses, we reached into our past as a film company to reintroduce some of these retro techniques to soften, diffuse, and creatively distort images.”

On the Netflix series, “The Haunting of Bly Manor,” cinematographers Maxime Alexandre AIC and James Kniest used a rear net, a black Fogal, to create an old Hollywood blooming effect—inspired by the photographs of George Hurrell, the master of old Hollywood’s glamour photography. When cinematographer James Kniest took over the show, he reduced the blooming effect by simply pulling the net tighter across the back of the lens.

Diopters, on the other hand, are another vintage filmmaking technique that can add the characteristics of an old-time lens, like donut bokeh and spherical aberration, which gives images a dreamy look. Diopters are optical elements that can alter the look of a lens without permanently changing the lens. Director Blake Farber and cinematographer Corrado Serri used a diopter to customize their recent Pepsi commercial. 

For the commercial, Farber and Serri chose the ALEXA Mini LF with the Signature Prime lenses, paired with ARRI’s TRINITY camera stabilization system to capture continuous movement and easily transition from high to low shots.

“The film’s original concept was to create a larger-than-life experience, traveling in many iconic locations within the region driven by music and energy,” says Serri. “But the pandemic and travel limitations led us to shoot the film in Dubai, with two days in studio and two on location. I felt the large-format frame would help bring this concept to life, giving us the extra resolution needed for the composite and set extension that CGI needed in some shots.”

Serri chose a -2.5 diopter with minimal lighting to create a vintage film characteristic.

“I saw some excellent films shot with the Signature Primes, so I knew their awesome character and what they could give to me. I did some tests with minimal light, focused on finding a way to add some defects and aberrations to the lenses, to obtain a more organic texture with a vintage taste. I found the best for our purposes was the -2.5 diopter, which added distortions on the sides of the frame. So the wider the lens, the more the distortion was present. It kept the center sharp and gave us some aberrations in the shapes of the bokeh.”

Serri used the diopter on all of the shots, except the product close-up and a few frames of the city skyline where CGI required clean images. The camera was set to an exposure index (EI) of 800 with a ½ low contrast filter and a T-stop between 2 and 2.8 to render a vintage filmlike aesthetic. Serri says, “the effect of the diopter was pretty consistent, creating distortion on the sides of the frames and in the bokeh of the lights. The effect was stronger on wider lenses.”

We had Serri break down the following shots:

Shot with the 35 mm Signature Prime, this frame is from the end of a long TRINITY tracking shot by operator Fares Corbani. Distortion from the diopter can be seen in the shape of the bokeh at the edge of the frame.

“At the beginning [of the shot], the guys walk under a softbox on a crane with a SkyPanel 360-C. They exit the overhead light and are silhouetted against the background lights. The wet floor enhances the light from the shop signs. At the end of the scene, the group is lit by the actual translucent machine, custom-built by [Production Designer] Gaspare De Pascali. I placed three LED lighting tubes inside the machine and had two electricians walking on the side of the frame with two tubes to add some kick from the side.”

In this frame, the diopter subtly softens the image. It stretches objects at the edge of the frame and introduces flares reminiscent of a vintage lens.

“The backlight and overhead Pepsi blue and red light were done with five Sola Frame LED moving heads and a laser prism projector overhead. Behind the set, which Gaspare De Pascali again built, I had three jumbo multi-source in the background. The white piano delivered enough bounce light on the piano player. I especially like how the diopter created an almost anamorphic-like distortion of the lines on the right side of the set.”

The diopter also helps enhance the flaring abilities of the Signature Prime lenses—creating a gentle specular flare at the bottom right of the frame.