August 24, 2018

How Full Frame & Super 35 Sensors Affect The Cinematography Process

Let's look at the visual results we get with larger sensors. 

We’ve seen our share of formats over the decades—Kinetoscope, Cinerama, Cinemascope, Ultra Panavision 70, IMAX—but out of all of them, Super 35 is probably the most popular among filmmakers since its debut in the early 1980s.

What we’re seeing today is the industry moving towards larger full frame sensors, or what we like to refer to as full format emerge. These are cameras with sensors approximately 36mm x 24mm, though they may be slightly larger or smaller (but below 65mm).

Discussions are shifting towards topics like,: “What’s the difference between Super 35 and full frame?” and “Which one should I use?” The latter has a simpler answer: Neither one is right or wrong. They’re tools.

Define your story. Choose the look you want. It doesn’t have to be one format throughout the entire process. 

Format, resolution, color bit depth, frame rate, lenses and camera type are all tools to tell story. Some tout advantageous attributes, e.g. recording a higher resolution like 4K so you can “punch in” or “reframe” during post when you’re delivering in HD or shooting RAW to maximize dynamic range for the color grade. Each project should have its own look and its own resonating visual grammar.

As a director, cinematographer, camera operator, and producer, don’t choose a look because it’s “what Sven Nykvist, Freddie Young, Roger Deakins or what any other cinematographer out there has done." Ask yourself WHY you should choose a certain camera, lens or resolution. WHY do we want a shallow depth of field? WHY do we need Steadicam at this moment? WHY do we need this framing?

Define your story. Choose the look you want. It doesn’t have to be one format throughout the entire process. Mix aspect ratios, mix resolutions, mix primes and zooms, mix anamorphic and spherical, mix film and digital. There are no rules. Well, maybe one: Don’t have shitty sound.

When it comes to choosing between Super 35 and full format, there’s a lot that can affect the cinematography process.

And YES, there will always be exceptions when you can’t choose, such as Netflix’s current 4K mandate, your budget sucks, you’re poor, etc. Try to choose everywhere you can. It will make you a better filmmaker.

When it comes to choosing between Super 35 and full format, there’s a lot that can affect the cinematography process. Both sensors are based on the size of 35mm film but full format is traditionally larger than Super 35. It begs the question, what kind of image results do these two formats produce?

Loren Simons, Sr. Field Applications Engineer at Canon USA, created a test using the Canon C700 FF and two lens focal lengths to show us. For Canon, he says, “Larger sensors means more real estate, which means we can maintain our optimal pixel pitch but still gain in overall resolution.”

 If you’re unfamiliar with pixel pitch, it’s the distance between pixels measured from the center of one pixel to the center of the next. The smaller the pitch, the higher the pixel density which yields a higher resolution. A higher pixel pitch creates a greater distance between the pixels and a lower resolution. However, higher resolution doesn’t always mean better.

Two viewpoints on the resolution topic come from Michel Cioni, Senior VP of Innovation at Panavision & Light Iron, where they discussed at Camerimage the difference (and importance) of resolution and sharpness. The other is cinematographer Steve Yedlin’s topic of ‘Why resolution doesn’t matter.” Both are worth a watch if you haven’t seen them.

Simons setup a live demonstration to help filmmakers better visualize how these different formats can be used. On one end was the Canon C700 FF mounted on dolly track and at the other end sat a model and back drop.

Spec wise, the Canon 700 FF has a 38.1mm x 20.1mm sensor and a 43.1mm image circle—18.69 megapixels (5952 x 3140) or 5.9K and a pixel size of 6.4 x 6.4 μm. Super 35 is cropped in-camera and there’s also a Super 16 mode. The lens used was a ZEISS 28-80mm T2.9 Compact Zoom. The point of the test is to illustrate the difference between full format and Super 35. 

Canon C700 FF – Full Format 
Lens focal length: 48mm
Distance from subject: 8 feet

Canon
Credit: Canon

Canon C700 FF – Super 35 
Lens focal length: 48mm
Distance from subject: 8 feet

Canon
Credit: Canon

When you look at the two images above, you can see the full format sensor shows a much wider image than the Super 35. Most of us already know this as Simons points out, “With the larger sensor, you’re scanning a larger portion of the image circle so you’re going to see more of the image.”

Does a larger sensor mean you’re getting a shallower depth of field? Simons notes, “That’s not inherently true.” Take a close look at the two images below:

Canon C700 FF – Super 35 
Lens focal length: 48mm
Distance from subject: 8 feet

Canon
Credit: Canon

Canon C700 FF – Full Format 
Lens focal length: 48mm,
Distance from subject: 8 feet, 1.45x Digital Zoom

Canon
Credit: Canon

When you look at these two images, you will notice that the second image is zoomed 1.45x digitally to match the frame size of the Super 35. You can also see that there’s no change in bokeh or image compression. Simons says, “The point here is to show you that the second image is simply scanning a larger portion of the image circle. No other characteristics are changing.”

Now let’s take a look at two different focal lengths in both formats and see how it affects the image.

Canon C700 FF – Full Format 
Lens focal length: 70mm
Distance from subject: 8 feet

Canon
Credit: Canon

Canon C700 FF – Super 35 
Lens focal length: 48mm
Distance from subject: 8 feet

Canon
Credit: Canon

Here, the full format image has a 70mm focal length and Super 35 has a 48mm focal length (but share the same distance). The framing on both sensors is the same but the bokeh of the full format is larger and we have a shallower depth of field. As Simons points out, “It’s not directly because the sensor is larger that gives us the shallower depth of field. It’s the fact that the larger sensor shows a wider field of view and that traditionally forces us to zoom the lens in optically to maintain the same framing. That's what gives us a shallower depth of field.”

In the next test, instead of zooming the lens in, Simons moved the camera closer to the subject. Check out the two images:

Canon C700 FF – Full Format 
Lens focal length: 48mm
Distance from subject: 6 feet

Canon
Credit: Canon

Canon C700 FF – Super 35 
Lens focal length: 48mm
Distance from subject: 8 feet

Canon
Credit: Canon
There are several things to notice in the images. The framing on both subjects is nearly identical. The depth of field change is minor. It’s a little shallower in the full format image because we are closer to the subject at 6 feet and therefore closer to the minimum focusing distance of the lens making the depth of field slightly shallower. 

“What’s really happening here is in the background and the foreground,” says Simons. “In the full format image, you can see a bunch of new lights near the top and bottom in the background. Take note of the green light on the top and the blue and yellow ones o then bottom. Notice the wall sconce that we see in the full format but not the Super 35. In fact, the inverse is happening in the foreground. You’re seeing less than what you’re getting in full format image than the Super 35 image.”

What’s happening here is what Simons describes as “The Revenant Effect.” Yes, the Alejandro G. Inarritu/Emmanuel Lubezki film starring Leonardo DiCaprio. Basically, by adjusting the position of the camera instead of focal length, you are bringing the foreground closer while pushing the background further away,  thus making it feel more expansive.

Keep in mind this test was done with the Canon C700 FF and a Zeiss. ARRI, RED, Sony, Panasonic, and everyone else in between may produce different results. At least, for now, you can generally understand what’s happening with your subject with larger sensors.

If you’re interested in seeing how other camera sensors work with different focal lengths, there are a few options. ARRI has a great tool called the ARRI Lens Illumination Guide and AbelCine created a handy field of view tool found here    

Your Comment

3 Comments

“In the full format image, you can see a bunch of new lights near the top and bottom in the background. Take note of the green light on the top and the blue and yellow ones o then bottom. Notice the wall sconce that we see in the full format but not the Super 35. In fact, the inverse is happening in the foreground. You’re seeing less than what you’re getting in full format image than the Super 35 image.”

But still if you use the Super 35 at 6 feet and put on 30mm lense you will get exactly the same image in terms of the DOF, size of the bokeh rings and field of view. Especially if you don't forget to adjust the f-stop (multiply it by 1,5 please?) to compensate it for the sensor size too.

So what's this article about? Sensors are tools, you got that right, but everything else...

For those only starting to learn such things this article can be misleading. It is a waste of time for the rest.

August 25, 2018 at 2:14PM

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Stass
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A more interesting analysis would be how sensor size affects content. Is there important information in the background that provides context? If you shoot hand-held and your subject is moving can you stay in focus? Do you need healthy zoom range without a huge, heavy and very expensive lens? Does your subject matter require unobtrusive equipment in order to maintain access? Check out the new generation of 1 inch chip cameras.

March 16, 2019 at 5:36PM

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If you were building a new lens kit would you go with Full Frame lenses or Super 35? I wish this article talked about that difference. Are they interchangeable? Are there limitations? With adapters and various mounts from manufactures how do you decide on Full frame or not?

April 24, 2019 at 9:15AM, Edited April 24, 9:16AM

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Dan Herrick
Owner/Executive Producer
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