ARRI has announced the new ALEXA 265. The new camera is 3x lighter and smaller than the existing ALEXA 65. Technology breakthroughs that were implemented in the ALEXA 35 allowed ARRI to essentially miniaturize the ALEXA 65 and come up with the ALEXA 265.
As the original ALEXA 65 is more than 10 years old, I think this was a good move by ARRI to create a newer, lighter version of the camera, with a lot of the same workflow and conveniences offered in the ALEXA 35.
This is a rental-only product and some people may be wondering why ARRI won’t be selling this new camera as we are starting to see a few forthcoming larger sensor cameras from Blackmagic Design and Fujifilm.
The ALEXA 265 is a new-generation 65 mm camera that has come to fruition from direct feedback from users of the ALEXA 65. The ALEXA 265 combines a small form factor with a revised 65 mm sensor, delivering higher image quality through 15 stops of dynamic range and enhanced low-light performance. The sensor is a revamped version of the existing ARRI A3X Rev.B CMOS sensor that is found in the ALEXA 65.
It features the same LogC4 workflow, REVEAL Color Science, and accessories as ARRI’s ALEXA 35, plus a new filter system, making the ALEXA 265 as easy to use as any other format.
ARRI ALEXA 265 
ARRI ALEXA 65
The ALEXA 265 camera body is based on the ALEXA 35 and despite containing a sensor three times as large, it is only 4 mm longer and 11 mm wider. Using this body design means ALEXA 265 is less than one-third the ALEXA 65’s weight (3.3 kg vs. 10.5 kg) and takes advantage of ARRI’s latest cooling and power management technologies.
The camera’s small size and weight allow it to be used in ways never imagined for 65 mm, including drones and stabilizers which was very hard to do with the original. The boot-up time and power draw have been improved, and compatibility with the ALEXA 35 accessory set opens up more rigging options.
Most of the current accessories that work with the ALEXA 35 will work with the ALEXA 265.
Revised 65mm Sensor
Cinematographers wanted to retain the 6.5K resolution and large pixel pitch, but they also wanted higher dynamic range and improved low-light performance. So what ARRI did was come up with a brand-new and comprehensive revision of the 65 mm sensor for the ALEXA 265. The dynamic range has been increased from 14 to 15 stops and the sensitivity from 3200 to 6400 EI (ISO/ASA), with what ARRI is claiming, are crisper blacks, greater contrast, and a lower noise floor.
If it ain’t broke, don’t fix it. The sensor is still based on the existing 65 mm format ARRI A3X Rev.B CMOS sensor with Bayer pattern color filter array that has a resolution of 6560 x 3100 54.12 x 25.58 mm / 2.130 x 1.007″ Ø 59.86 mm / 2.357″ with a photosite pitch of 8.25 μm, however, according to ARRI they have made both hardware and software revisions.
ARRI couldn’t just stitch three ALEXA 35 sensors together because the design of that sensor doesn’t allow for that. Coming up with a new sensor would have been very difficult and because the existing A3X was so good it made sense to keep using it.
The camera can record:
- ARRIRAW 6.5K 2.12:1 Open Gate: 6560x 3100
- ARRIRAW 5.1K 1.65:1: 5120 x 3100
- ARRIRAW 4.5K LF 3:2: 4448 x 3096
The following frame rates can be recorded:
- ARRIRAW 6.5K 2.12:1 Open Gate: 29/60 fps
- ARRIRAW 5.1K 1.65:1: 37/60 fps
- ARRIRAW 4.5K LF 3:2: 43/60 fps
Reveal Color Science, LogC4 workflow & Codex Compact Drives
The new-generation LogC4 workflow and 3D LUTs introduced for ALEXA 35 are now shared with ALEXA 265, which records ARRIRAW in-camera to the Codex Compact Drives used in all current ARRI cameras. Standard drive readers and docks can be used, as can Codex HDE (High Density Encoding), reducing file sizes by up to 40% without diminishing image quality. On-set monitors can be set up in HD or UHD, displaying SDR or HDR, or both. ARRI is updating its SDK to ensure that ALEXA 265 images are compatible with all major third-party software tools.
ALEXA 265 images are processed in-camera using ARRI REVEAL Color Science, introduced with the ALEXA 35 and also compatible with ARRIRAW images from the ALEXA Mini LF. REVEAL is a suite of image processing steps that collectively help the camera to capture more accurate colors, with subtler tonal variations. Skin tones are rendered in a flattering, natural way, while highly saturated colors and challenging colors such as pastel shades are displayed with incredible realism. All ALEXA 265 and ALEXA 35 cameras are super color-matched to each other, simplifying color grading, and the ALEXA 265’s advanced LED calibration streamlines virtual production and LED volume work.
Having extra dynamic range, better contrast and better noise suppression are only parts of the puzzle. Image processing is the next big step and this ultimately goes a long way toward determining what your images will look like. The sensor is just one piece of the puzzle. and you can’t complete a puzzle if you don’t have all of the pieces.
Over the last few years, ARRI color scientists have looked closely at the processing and spent a lot of time talking to DPs, colorists, and post supervisors to get a better picture of what could be improved.
This led to the creation of what ARRI calls the Reveal Color Science. Yes, this is just a marketing term, but what it actually does is a very important step in the overall creation of the image.
So what is the Reveal Color Science and what does it do? The Reveal Color Science happens in thecamera. ARRIRAW goes through the Reveal Color Science pipeline and then the ProRes recordings are created and the various outputs can be displayed in the viewfinder, SDI outputs, and frame grabs. Now, if you shoot ARRIRAW, you will be seeing images processed with Reveal Color Science on your monitor, but the heavy lifting is done later on. You can then utilize the new ARRI Reference Tool (ART) software or programs like DaVinci Resolve, FilmLight, Colorfront, etc. to process your images with Reveal.
So what exactly is it? Well, Reveal Color Science consists of quite a few different processes. The first is a new ARRI Debayer algorithm called ADA-7 which converts ARRIRAW into camera native RGB image data. ADA-7 is a much more powerful algorithm than ARRI has used before and this is only possible because of the increased processing power in the ALEXA 35 and ALEXA 265. ADA-7 now provides cleaner images and cleaner edges when working with green or blue screens.
When the ARRIRAW is Debayered into RGB image data it is literally just a cloud of points of color values that represent what parts of the spectrum the sensor is sensitive to. You can’t do anything with this information, yet, because this is just the first step. So what comes next?
Well, now that you have this representation of what the sensor is seeing, you need to do something with it, and that means converting it into a color space. Ideally, you want to put it into a color space that is a good representation of what the human eye sees.
With this in mind, ARRI has come up with what they call ARRI Color Engine ACE4. This is not a traditional matrix and what that means is that it is able to more accurately recreate nuanced colors. It also allows for better skin tone reproduction and better chroma tracking across different exposure levels. If you underexpose or overexpose your image, once you correct that footage the colors remain true without skewing and changing. This is where other cameras fall over.
The ARRI Color Engine ACE4 also helps with creating more deeply saturated colors when shooting objects like neon signs, brake lights, or anything else that has very strong colors. Usually, these are the type of things that never quite look right when you are shooting with a digital camera. All of these processes make a huge difference in the real world, however, nobody ever talks about them in clickbait videos on YouTube where someone compares an iPhone with an ALEXA.
The other benefit of the new color engine is if you are filming in low key scenes such as overcast days you can get better colors and better color differentiation. This is very evident when using the camera. Saturated colors still stay nice and saturated regardless of the conditions you are shooting in. Even in mixed lighting conditions, you get accurate color rendition without things starting to look wrong.
So how does this new color engine work? Well, the RGB image data is placed in a new color space called ARRI Wide Gamut AWG4. If you are not familiar with what a color space is, it is a method for writing down colors as numbers in order to store, process, and display images. There are two different types of color spaces, scene-referred color spaces, and display-referred color spaces. Display referred color spaces you may be familiar with are Rec.709, P3, and Rec.2020. Scene-referred color spaces are not limited by display technologies and they are optimal for capturing more color information. Scene-referred color spaces are spaces like ARRI Wide Gamut and ACES.
You would think that the bigger the scene-referred color space, the better, but this is not the case. The trouble with scene-referred color spaces is that they contain ‘virtual’ colors that are outside of the human spectrum and we can’t actually see them. The other problem with ‘virtual’ colors is that they can result in negative values and some post-production programs see these negative values and then just place them at a value of zero which results in gamut clipping. This is why capturing ‘virtual’ colors is not ideal. Bigger isn’t always better.
Above is the spectrum of colors we can see (the horseshoe shape) and how that compares to color spaces like ACES, Rec.2020, and Rec.709.
Now, if we look at ARRI Wide Gamut AWG4 you can see that it is slightly larger than Rec.2020, but not too large that it introduces too many ‘virtual’ colors that can’t be seen by the human eye. One of the main reasons you don’t want to capture too much extra blue/green color information that the human eye can see is that it makes it harder for a colorist to grade footage. Eyes are not cameras and cameras are not eyes. What they both see is different and it is a fine balancing act to get a good compromise that works well for both.
ARRI Wide Gamut AWG4 is fully enclosed and compatible with ACES. ALEXA Wide Gamut, used on all previous ALEXA cameras, was not fully enclosed by ACES and required extra processing steps to prevent strange color processing.
Unfortunately, at least at this point in time, the ALEXA 265 doesn’t have the ability to use textures like the ALEXA 35. There is also no ES EI modes like are available in the ALEXA 35.
Filter Cartridge System
The existing ALEXA 65 had an Internal Filter Module (IFM) option, however, you needed to remove the lens and insert the ND filters from the front which was far from ideal. ARRI went back to the drawing board and came up with a filter cartridge concept.
A unique feature of the ALEXA 265 is its filter cartridge system, which allows special filter trays, encased in a protective cartridge, to slide in front of the sensor. ARRI FSND filters from zero to ND2.7 in single-stop increments will be available with ALEXA 265 at the time of launch, and many more creative filter options are in the works. An encoded chip on the filter tray conveys information about whatever filter has been inserted; this information is available in the user interface and is also recorded in camera metadata for use on set and in post.
Prominent filter manufacturers are currently looking into making filter cartridges that will be able to be used in the ALEXA 265.
Inputs & Outputs
Monitoring options are much improved over the previous ALEXA 65 as there are now UHD outputs with 1.5G, 3G, 6G and 12G options and the ability to monitor in SDR or HDR.
The ALEXA 265 offers a host of inputs and outputs for all your accessories. Highlights include two completely independent 12G SDI outputs, an Ethernet connector for real-time streaming metadata, and regulated 12 V and 24 V accessory power outputs. Essentially the outputs and inputs are identical to that of the ALEXA 35.
Modular power and B-Mount battery interface
The Power Distribution Module PDM-1 (center) offers seven extra power accessory outputs, while B-Mount is the latest 24 V onboard battery standard, with improved mechanics, impressive metadata, and enough power for all your accessories.
Integrated motor controller and radio module
A built-in motor controller with LBUS connectivity facilitates uncluttered camera builds. An integrated EMIP radio module provides connectivity to ARRI ECS hand units including the Hi‑5, WCU‑4, SXU-1, and ZMU‑4. Should an external controller be required, the RIA‑1 integrates directly with the camera via LBUS.
Available early 2025
The list of ALEXA 65 films and filmmakers over the last 10 years is a roll call of the industry’s most visionary projects and people. While 65 mm may only be accessible to relatively few productions, this historic format inspires many and represents the pinnacle of mainstream image acquisition.
ALEXA 265 will be available to productions from early 2025.
Specifications
It’s been 10 years
On 21 September 2014 at the Cinec convention in Munich, ARRI announced the ALEXA 65, a 6K 65mm digital cinema camera.
The camera features a sensor that is slightly larger than a 65mm 5-perf film frame and is comprised of three ALEXA sensors that are arranged vertically and seamlessly stitched together.
Image credit: ARRI Rental
The ALEXA 65 subsequently became the go-to large-format solution for high-end theatrical motion pictures. The cameras are only available through ARRI Rental. The ALEXA 65 has become so sought after that there is and continues to be a long waiting list for anyone who wants to use one.
The camera has been used on films such as The Revenant, Parasite, Wonder Woman, Mission Impossible – Rogue Nation, Transformers – The Last Knight, Okja, Roma, Rogue One, The Dark Tower, War For The Planet Of The Apes, Life, Dune, Dune II, The Joker, The Batman, Thor – Ragnarok, Furiosa: A Mad Max Saga, Barbie, and ll Quiet on the Western Front just to name a few.
Only 70 ALEXA 65’s were made.
ARRi Rental also provides a wide array of lenses that will cover the ALEXA 65’s large sensor.
The Modern Digital Industry Standard
The ALEXA has become the modern digital industry standard in many ways. The cameras have been used in high-budget feature films, television shows, and commercials by some of the world’s leading cinematographers. Since 2010, a variety of ALEXA camera models have been introduced, including the ALEXA LF and ALEXA Mini LF, and ARRI Rental’s exclusive ALEXA 65.
Here are all of the ALEXA models that have been released to date:
- ALEXA
- ALEXA Plus
- ALEXA Plus 4:3
- ALEXA M
- ALEXA Studio
- ALEXA HD
- ALEXA HD Plus
- ALEXA XT
- ALEXA XT Plus
- ALEXA XT M
- ALEXA XT Studio
- ALEXA SXT EV
- ALEXA SXT Plus
- ALEXA SXT Studio
- ALEXA SXT W
- ALEXA 65
- ALEXA Mini
- ALEXA LF
- ALEXA Mini LF
- ALEXA 35
- ALEXA 265
The science of the sensor
All ALEXA cameras, except the ALEXA 35 feature a variation of the same sensor. The ALEXA ALEV III 3392×2200 (28.17×18.13mm) sensor has a pixel size of .00825mm, and even today, more than seven years after it was first announced, it’s still considered one of the best sensors on the market. This is a true testament to just how good this sensor is. The ALEV III sensor oversampled images intended for HD or 2K distribution. This oversampling has become commonplace amongst manufacturers who build sensors for digital cinema cameras.
One of the reasons the ALEV III is slightly larger than a Super 35 frame, was so users could see 10 percent beyond the edges of the recorded frame. This capability is crucial so you can see what is going to come into frame. At the time this functionality was only available to optical viewfinders but was unheard of in any type of electronic viewfinder.
Unique for a digital sensor was the height of the ALEXA sensor, which allows a number of sensor modes only available in ALEXA cameras, including those needed for shooting with anamorphic lenses. The sensor’s 3.4K horizontal photosite count delivered unusually large photosites for an optimal balance between image sharpness on the one hand and high dynamic range, high sensitivity, and a low noise floor on the other.
Although the science behind the breakthrough performance of ALEXA’s custom-designed CMOS sensor is complex, the use of large photosites and a Dual Gain Architecture are its two main principles. By employing unusually large photosites (in today’s world of tiny cell phone sensors), ALEXA’s sensor exhibits high dynamic range, high sensitivity, and low crosstalk. The larger a photosite is, the more light it can capture, and the lower the noise.
The Dual Gain Architecture simultaneously provides two separate read-out paths from each pixel with different amplification. The first path contains the regular, highly amplified signal. The second path contains a signal with lower amplification, to capture the information that is clipped in the first path. Both paths feed into the camera’s A/D converters, delivering a 14-bit image for each path. These images are then combined into a single 16-bit high dynamic range image. This method enhances low light performance and prevents the highlights from being clipped, thereby significantly extending the dynamic range of the image.
The fact a sensor that is 14 years old is still considered by many to be the benchmark in the industry is a testament to just how good it was and continues to be.
