FILM STYLE SLOW MOTION WORKS
because it is very different from video style slo motion
Let's start with film, since that is where the concept of slowing down action began. It's important to note that film has a time base of 24 frames per second. This means that a camera and a projector are both "clocked" to capture and playback 24 frames in one second.
The projector has a constant
timebase in that the projector always plays back 24 frames per second.
As camera technology began to improve, it was discovered that if you moved the film through the camera faster while recording, say at 48 frames in one second instead of 24, then when it played back on the projector, the footage played back at half the speed. Twice as many frames were being recorded in one second giving you slow motion effects.
Interesting fact: the original standard for film was going to be 48 frames per second but it literally doubles the cost, size and weight of everything, 24 frames was chosen because it had the most tolerable amount of flicker that the human eye can handle. Now, with digital, people are beginning to think about 48fps again for 3D films.
A RED camera treats over cranked footage exactly as film. This is how it works:
- The timebase is 23.98 (film is 24)
- The number of frames you shoot in the time base is the over or under crank. Let's use 72fps as an example.
The RED captures 72fps (in 23.98 timebase) instead of the regular 24 fps in (23.98 timebase) so that when you play back the footage in a 23.98 timeline, you see it plays the 72 frames per second in a 23.98 time base the way film does. For example, if you record for one second at 48 frames per second it takes two seconds to play the footage back. Here is a chart to help illustrate this:
Slow Motion: time in seconds of footage recorded at different fps compared to acquired time in seconds of footage in slo mo.
- 1 second @24 FPS= 1 second clip duration plays back for 1 seconds in a 23.98 timeline
- 1 second @48 FPS= 2 second clip duration plays back for 2 seconds in a 23.98 timeline
- 1 second @72 FPS= 3 second clip duration plays back for 3 seconds in a 23.98 timeline
- 1 second @96 FPS= 4 second clip duration plays back for 4 seconds in a 23.98 timeline
- 1 second @120FPS= 5 second clip duration plays back for 5 seconds in a 23.98 timeline
It is evident that with RED or FILM
, over cranking the camera is actually capturing more frames in one second. This is the exact principle the SUPER
high speed cameras like Weiss Cam and Phantom use, as well. These cameras are capable of capturing up to 1000 or even 4000 frames in one second. That means (with enough light) they can "see" a bullet flying through the air.
Film works in exactly the same way. It captures more information in the same time base. One second is always one second, you are just telling the camera to capture MORE FRAMES
in that one second, so in film and
RED you are simply capturing more information and you do not need to do anything other than drop the footage into a 23.98 time base.
What happens in a 5D (or Panasonic HVX 200) is that they use the sensor's 60 frame clock speed to capture the extra frames. While the footage is being recorded, frames are marked for processing. Through a special process, the footage is extracted and the frames playback as slow motion in a 23.98 timebase. (99.9% of all video based editing is 23.98 and NOT
There are other methods of extracting slow motion from shot footage which involve post production tools, such as Adobe After Effects
with retiming software like Twixtor
from RE:Vision Effects. This combination can produce super slow motion effects but it is all with interpolated frames. This is where capturing slow motion and creating slow motion vastly differ. In addition, while Twixtor is a powerful tool, not all footage is suitable for Twixtor because it uses color maps and intelligent pixel interpolation to draw the frames that do not exist.
Another in-camera method is to capture at 59.94. Shane Ross offers an excellent video tutorial podcast at the COW that shows you how to convert 720p60 footage into very smooth slow motion using the CONFORM option of Cinema Tools.
My advice when capturing 59.94 is to capture progressive frames; this way the footage can be interpolated back to 23.98, a pulldown can be added and a slow motion effect can be created by telling the software that the footage is 23.98. When it sees 60 frames, it plays them back at 23.98 speed. Here again, the limitation is 60fps slow motion. If you wanted to make that 120fps slow motion, you would only be doubling frames instead of playing back 120 unique frames -- you would be playing back every frame twice to simulate a slow motion effect.
There is a big difference between in-camera Film Style Slow Motion
and this method. Remember that with film style slow motion, the camera is capturing every frame, whereas in post-produced slow motion, the frames are being interpolated.
I hope this clears up an often-asked question here at the COW, and helps those who may not have worked with film understand how slow motion works in the digital environment.
My best advice before you go out and shoot: test and consult.
Links -- Check this out! http://vimeo.com/10567176
Or this for some under crank
|Related Articles / Tutorials:|
RBG's DP: Claudia Raschke, Ruth Ginsburg & Canon C300 Mk II
In his conversation with Claudia Raschke, the cinematographer of the acclaimed documentary "RBG" featuring Supreme Court Justice and folk hero Ruth Bader Ginsburg, DP Jimmy Matlosz speaks to her about the Canon C300, the challenges of shooting such a high-profile subject, and the influence of dance on her approach to documentary filmmaking. A truly remarkable conversation about multiple remarkable subjects.
Feature, People / Interview
Get The Shot Without Getting Shot: Adventures in Stock Video
Rick Ray of DVArchive has traveled the world, lived in a Buddhist monastery in Thailand, played ragtime piano for money in Australian bars, and both been arrested in Ethiopa and recruited those same police to be in his videos the very next day. In his NAB Show presentation for Adobe Stock, Rick gets specific about how to make real money in stock video following your passion around the world, what kind of equipment to choose and avoid, and yes, some advice about talking your way out of trouble.
Go Creative Show: The Cinematography of A Quiet Place
Charlotte Bruus Christensen is the Danish cinematographer behind the lens of the horrifying and beautifully shot film A Quiet Place. Charlotte joins commercial director and Go Creative Show host Ben Consoli to discuss the camera, lighting, and lensing choices for A Quiet Place, its unique sound design and how show created its horrifying yet warm look.
How Kubrick Achieved the Cinematography of Barry Lyndon
Stanley Kubrick’s Barry Lyndon is often lauded as one of the greatest achievements in the history of cinematography. And in a decade or even a year with some of the toughest competition imaginable, Barry Lyndon always seems to stick out just a little bit more. What sets the cinematography of Barry Lyndon apart from other movies? And how was it done? Let's explore the story...
Robert McLachlan: Cinematographer for Game of Thrones
Robert McLachlan is the cinematographer of Game of Thrones, Westworld and Ray Donovan, and he joins commercial director and Go Creative Show host Ben Consoli to share behind the scenes stories from some of his most iconic scenes including The Red Wedding and The Loot Train Battle.
Feature, People / Interview
DJI Mavic Pro In Depth Review - The Best 4K Drone?
VFX guru Tobias Gleissenberger was so delighted with the DJI Mavic Pro 4K drone that he bought (yes, bought) that he was inspired to take a break from making tutorials to create an in-depth review of this compact, lightweight, consumer drone offering terrific value. No, it's not a platform for your digital cinema camera, but if you're looking for a fast, fun, integrated 4K camera drone packed with features, the Mavic Pro might be for you. This review is delivered Surfaced Studio-style, with wit, high energy, and details you won't find anywhere else.
Beautiful 8K Timelapse of Norway's Four Seasons
One year of planning, one year of shooting, and four months of post-production is a lot of time to spend on a single timelapse, but photographer Morten Rustad‘s creation SEASONS of NORWAY captured this 8K masterpiece by travelling a total of 20,000
Join Go Creative Show host, Ben Consoli and his special guest, David Klein, ASC, cinematographer of Homeland and True Blood. David is here to talk all about it all. His love of realism has defined a generation of filmmaking and he continues to execute it flawlessly with his work on Homeland. David talks with us about all his gear and lighting choices, shooting hand-held effectively and how the best film education is to simply shoot something.
Feature, People / Interview
All Eyes on IBC 2016 for Cameras and Lenses Galore
What’s that you say? An IBC that’s not only relevant, but downright exhilarating?
This used to not be news, of course. However, in recent years, IBC has too often become simply an opportunity for European audiences to see products already announced at NAB. In 2016, however, the focus swings sharply to Amsterdam, especially when it comes to cameras and lenses. IBC 2016 is shaping up to be one of the most dramatic trade shows for cinematographers, broadcasters, and videographers in years. Join Creative COW Editor-in-Chief Tim Wilson for a speedy overview of some of the highlights.
Depth of Field: Gregg Toland, Citizen Kane and Beyond
Whenever somebody equates "shallow depth of field" and "cinematic look," it's important to remember that the opposite is also sometimes true. Creative COW Editor-in-Chief Tim Wilson celebrates the work of Gregg Toland, ASC, born this week in 1904 -- the first master of extreme depth of field in movies like Citizen Kane and The Grapes of Wrath that forever changed what is possible for humans to do with cameras. This reprise of a classic article from the Creative COW Archives also offers a look at what Toland's approach to cinematic composition can mean for YOUR shooting.