Digital Full Gate Anamorphic

There is a revolution growing with a modern take on Anamorphic optics in cinema. A growing list of manufacturers are producing new exciting gear to offer new options to productions. CinemaScope as it was originally called offered the audience a peripherally fulfilling experience. It also compensated for less than ideal film grain by using more of the negative surface. Today, these advantages can still apply.

Here are the basics. Anamorphic optics are fairly complex and hard to manufacture. The basic concept is a curved optic that compressed the image horizontally. This allowed the use of the extra space above and below. This allows the use of the 1.33:1 (4:3) aspect or the full gate. (The maximum film surface that can be exposed in a film camera)
The projectionist would then use a lens that would stretch the image out.

1.78:1 (16:9) on film:

1.78:1 (16:9) projected:

1.33:1 (4:3) anamorphic on film:

2.39:1 anamorphic projected:

Initially Cinematographers tried to hide the image anomalies inherent with the poor performance of anamorphic optics. These include: poor close focus performance, blue horizontal streaks in strong highlights, geometric distortion or curving on horizontal lines, vertical stretching on out of focus areas, chromatic aberrations,  shallow depth of field, soft at the edges, oval flares, ghosting, breathing while focusing. Now the aberrations are embraced as a look, and why not, it looks fantastic.

Cameras and lenses have become remarkably clean and sharp. In many cases Cinematographers are looking at ways to bring life back into the image and get away from the ultra clinical clarity. Old lenses, removed coatings, nets, fishing wire glued behind the lens, and of course, anamorphic lenses are quickly gaining popularity.

Manufacturers are starting to respond to this growing demand. Angenieux  has a beautiful anamorphic zoom lens,  Cooke has a new anamorphic prime set. Cooke and Angenieux even partnered to come out with a cohesive look. Zeiss has a new Master Anamorphic lens set on the way, scorpio/ service vision also has a new set of anamorphic primes coming soon. And although these new lenses are very clean, they still offer a lot of the beauty of anamorphic and the wider coverage on the capture area.

Capturing these lenses with a digital camera is not as simple as it may seem. Almost all digital cinema cameras on the market today have a 16:9 sensor. To use the lens, only the center of the sensor gets used. Even though the full sensor is captured, to stretch the image 2x wide and de-squeeze the optical effect, the aspect ratio would be about 3.55:1 ultra ultra wide. the image has to be cropped to the expected 2.39:1 ratio. Essentially we only use a 4:3 extraction of the sensor. The problem with this is that most of the effect of the lens happens at the edges and the horizontal resolution suffers. The image below illustrates this. There are 1.3x anamorphic lenses on the market designed to work with 16:9 sensors, but these have a reduced effect with less extreme optical compression.

(ARRIRAW Resolution shown)

Arri is the only camera manufacturer with a current line of digital cameras that have a 4:3 full gate sensor.  (Arri’s D-21 and the Weisscam also have a 4:3 sensor).
The larger capture area, like on 35m film, has the advantage of more light capture area and more resolution.  2880×2160 vs 2880×1620.  If you take the 2880 width and pixel double in post to counteract the optical compression, you end up with 5760×2160, or at least a good 4k release potential out of an Alexa.

Looking forward to the future, I had the fortune of attending the Cooke Dinner at NAB this year. Dave Stump asc stood up and asked “why are we throwing away 30 percent of the pixels on every projector that shows an anamorphic movie in America and, for that matter, in the world? We show an anamorphic movie 858 pixels high on every 2K DCI projector.” (as quoted by Film and Digital Times). His question really rounds out the potential of anamorphic cinema with today’s technology.


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