ARRI Rental DNA LF

If you dream of tuneable, repeatable vintage looks for Large Format/Full Frame, look into ARRI Rental’s DNA LF Primes.

It’s one thing putting an LPL mount onto an ancient optic. It is an altogether different experience having access to more than 22 sets of 9 DNA LF lenses that match, can be tuned, restored to normal, and retuned again to the same or different specifications. You can do this at ARRI Rental facilities in Munich, Berlin, London, Burbank and New York.

Picture prepping at ARRI Rental London. Three months later, you get the dreaded word: “reshoot.”  The location has moved to Hollywood. But, you are confident in the knowledge that ARRI Rental Burbank has the same tuning and calibration equipment as London. The DNA LF lenses you had in London can be re-tuned in Burbank to the same specifications because they have  been carefully calibrated. You don’t even need the same serial number. 

Optical designers know that “if you cannot measure it, you cannot build it.” Each ARRI Rental facility in Munich, Berlin, London, Burbank and New York is being outfitted with a custom-designed Trioptics MTF optical testing device.

How are lenses tuned, detuned, customized? The process is almost the opposite of optimizing for maximum performance in manufacturing. Lens designers may weep when they see this.  In the eternal quest for individuality and creative distinction, cinematographers and their favorite lens gurus can deconstruct “perfectly good” lenses to change: 

  • field curvature (focus at the edges of frame), 
  • focus fall-off (how gently or abruptly the out-of-focus area becomes softer), 
  • halation (glowing highlights), 
  • contrast (how rich shadows are), 
  • spherical aberration (decreased sharpness) 
  • and more. 

Previously, the process may have been random and not necessarily repeatable. You repositioned internal elements and air-gaps with shims, set-screws and days of trial and error.

As with ALEXA 65 DNA lenses, ARRI Rental rehoused vintage lenses in modern DNA LF housings. Elements were recoated for consistency of color and flare, internal adjustments calibrated, irises replaced. Millions of dollars were invested in the latest test equipment at each major ARRI Rental facility. 

Note that ARRI Rental ALEXA 65 Prime DNA lenses cover a 60 mm image circle. ARRI Rental DNA LF primes cover a 46 mm image circle.

Evening sky over RAI, the convention halls of IBC. Shot with ARRI Rental DNA LF 35 mm at T5.6. The lens has been tuned to accentuate field curvature. Notice how the image is softer at the edges than the center.

It was time to put DNA lens theory to the test. Andrew Prior, Head of Camera Technology and Development at ARRI Rental UK hand-delivered a 35 mm T2 DNA LF prime to IBC this September. The idea was to try this lens in Amsterdam. Then, rent a fast BMW X5 at Sixt Car Rental in the RAI Convention Center and drive 814 km to ARRI Rental in Munich. It is not a fun drive: 220 km/hr one minute, crawling along single-lane construction zones behind diesel-belching trucks the next. 

Above, several lens groups removed, the DNA LF 35 mm is ready for further tuning. Calibration mechanics and markings inside the housing make this a repeatable affair.

ARRI Rental designed special tools to dismantle each lens in the set. The DNA LF 35 mm delivered from Amsterdam is about to be dissected, above.

Mark Hope-Jones, Content Marketing Manager of ARRI Rental, was waiting in Munich. It was a quick and easy process to tune a completely different  35 mm  DNA LF to the very same tolerances and with the same look. Manfred Jahn, Head of the ARRI Rental Camera Department in Munich, explained all the different degrees that DNA LF lenses can be tuned, detuned, distressed, restored.  

A seriously de-tuned Manfred Jahn, taken with ARRI Rental DNA LF 35mm at T2. Focus on his shoulders fall off gently. The bright exterior adds ghosting to his dark shirt.

Lens technician Christian Millim taken with DNA LF 35mm at T2. The ARRI Rental logo is glowing with halations.

Lens technician Patrizia Starke assembling a DNA LF. Taken with DNA LF 35mm at T2. Her right eye is sharp, but focus falls off gently everywhere else.

Christian Agerer taken with DNA LF wide open at T2, with focus fall-off, shading and ARRI Rental logo almost “vibrating.”

As seen with a DNA LF tuned for extreme field curvature, this is the ARRI Rental lens assembly and adjustment room. In addition to tuning and detun- ing DNA lenses, ARRI Rental can also work with clients to customize Signature Primes, Master Primes, Ultra Primes and more.

The DNA LF lens concept is a unified set of mechanical housings designed and made by ARRI Rental. Carefully sourced vintage optics are rehoused into these modern lens housings. Elements come from a curated collection from the late 1950s to the late 1970s.

Elements are assembled into lens groups that are designed with calibrations for repeatable tuning by ARRI Rental facilities worldwide. New iris assemblies provide smooth, round bokeh and fast apertures of T1.5 to T2.

Focus scales for each lens are calibrated individually, by hand, before engraving the focus rings.

Internal lens metadata rings and electronic sensing modules are installed.
DNA LF lenses come in LPL mounts with LDS-2 contacts.

Christian Agerer “driving” the custom-designed Trioptics MTF optical testing device. As mentioned, each ARRI Rental facility in Munich, Berlin, London, Burbank and New York has commissioned one of these. ARRI Cine Technik also uses this machine in manufacturing and QC of Signature Primes. In this photo taken with an ARRI DNA LF 35mm at T2, note how the extremely tuned field curvature blurs and distorts the keyboard, above at right.

In addition to having a Trioptics MTF Tester, ARRI Rental offices world-wide use the same DENZ MFC 65 lens projector.

Each ARRI Rental office also receives a case with custom tools to adjust and tune every focal length in every set.


DNA LF Prime Specifications

Leave a Comment

Tags: , , , , , ,