I Screen, You Screen, We All Screen for Green Screen
What did you do last week? I mercilessly tore my living room apart and temporarily transformed it into a green screen (a.k.a. “chroma key”) studio in which I directed a short comedy called 2084. For as long as I can remember, my friends and I have joked about shooting 2084 on a massive soundstage with high-end gear and a huge crew — total overkill for this very silly, 3-minute short. Well, after ten years of that not happening, we finally decided to shoot 2084 with a tiny crew (four of us) and a budget just large enough to cover lunch.
While I didn’t shoot the film with my iPhone (I used a Blackmagic Cinema Camera), I did rely heavily on my iPad to improve the quality of my green screen. I’ll explain how in just a moment, but first I want to give you a quick green screen overview. Skip ahead if you’re already a green screen pro… or hate zombie jokes.
To get started, actors (or other foreground elements) are shot in front of a large green background (a “green screen”). Then, in post-production, the green areas are digitally removed, allowing the actors to be combined with other layers of imagery. This process is called compositing. For example, you might shoot your friend standing in front of a green screen looking profoundly concerned. Then, in your compositing application (i.e., Adobe After Effects, Nuke, Apple Motion, iMovie for Mac, etc.), you would remove the green, add a new background, and make it appear that your friend is standing on a cliff, observing an approaching army of mutant-spider-riding zombie pirates! (Mutant Spider-Riding Zombie Pirates copyright 2014 Taz Goldstein… maybe.) Green screen photography is a crucial component of nearly every big-budget summer blockbuster, but it’s based on the same technology that places cheesy meteorologists in front of cheesier weather maps!
Before you ask, yes, other colors can be used. “Blue screen” is quite popular, and I’ve even shot on an orange screen. That said, green is the most common. As you might expect, professional (and expensive) green screen materials, paints and surfaces typically yield the best results. However, with lots of patience and practice, you can achieve amazing results with much less expensive alternatives.
Now that you understand the basic concepts, you need to understand the biggest problem filmmakers face when shooting green screen — uneven lighting.
To perform properly, green screens must be evenly lit. Why? Because its much easier for editing or compositing applications to remove a narrow range of green shades, rather than a wide range. To put it over-simplistically, if your green screen is evenly lit across its entire surface, the computer sees it as a single shade of green, which requires less effort to remove. If your green screen is unevenly lit, with light and dark areas, the computer sees it as multiple shades of green, making it harder to remove. The harder your green background is to remove, the rougher and more obvious the edges of your composited subjects will appear, making everything look green screened and completely fake, as in, “Dude, that astronaut looks green screened and completely fake!” So, how can you quickly ensure your green screen is evenly lit? With your iThing, of course!
The simplest, fastest and coolest way to identify uneven green screen lighting is with an awesome app called Green Screener ($9.99). To get started, you simply position your iPhone or iPad in front of your set, pointing its camera towards the lit green screen (tripod mounts from Studio Neat, Square Jellyfish and Padcaster are quite helpful for this sort of thing).
After launching Green Screener, your iThing will display a gray-scale image of your set. The app instantly identifies different luminance (brightness) ranges of your green screen and displays them as clearly delineated gray bands. Darker bands represent darker areas of your green screen, while lighter bands represent the lighter areas. Moving your lights around will cause those bands to move around the screen. Simple, right?
If you tap one of the gray bands on the screen, it turns green — this is now your target luminance. As you reposition your lights, bringing each area of your green screen into the target luminance range, it turns green on your device’s display. The idea is to turn as much of your device’s screen green as possible. Think of it as a carnival game: Move the lights, turn everything green, win a crappy stuffed toy (and an evenly lit green screen)! Yes, I’m simplifying the process a bit, but not by much. It really is a matter of setting a target, and then moving lights to match it. With an evenly lit green screen, your final composites stand a much better chance of looking silky smooth and artifact free.
Green Screener saved my bacon during last week’s shoot — or should I say, it helped keep my bacon from needing to be saved. I truly love this app. Still not convinced of its supercalafragalisticness? Consider this: The app was invented by Per Holmes, the same guy who gave the world Shot Designer, “Hollywood Camera Work” and “Visual Effects for Directors” (a brilliant training series that I consider required viewing for all filmmakers who are serious about visual effects). Bottom line: If you own an iThing, and you light green screens, get Green Screener.
More green screen fun coming next week when we take a look at an app that will help you line up your green screen shots, and even composite green screen video right on your iDevice! Just think of all the moon landing videos you can fake right from the comfort of your own underground government compound!
by Hollywood Camera Work LLC
Get amazingly perfect green screen with Green Screener.
See demonstration video at www.hollywoodcamerawork.com
For good chroma keying, green/blue screens must be extremely even, or fine edge detail like hair and transparency starts to become blotchy, which is the hallmark of bad green screen.
Invented by Per Holmes, creator of the Hollywood Camera Work training, Green Screener is a new kind of tool for lighting a green screen that breaks your green screen up into bands, so you can easily see how to light it.
Whether you're working on a $100M blockbuster or shooting green screen in your basement, Green Screener will raise the quality of your green screen to a new standard.
by Hollywood Camera Work LLC
"A great App for Directors and DP's alike! Lightning fast shot designs. Don't be without it on the set." -- John Badham, Director, Saturday Night Fever, WarGames
"Excellent tool for planning my scenes fast!" -- Clint Reagan, Previz Supervisor, Hunger Games, Prometheus, Knight & Day, GI Joe
WHAT IS SHOT DESIGNER?
• CAMERA DIAGRAM - Shot Designer dramatically speeds up the Director's process of making camera diagrams. Create full-blown diagrams in seconds. The software does most of the work.
• ANIMATION - Animate your characters and cameras to move around your diagram in real-time. Previsualize the rhythm of a scene by seeing it play out.
• SHOT LIST - The integrated Shot List is tied into the diagram and writes itself while you work. Edit shots intuitively in the diagram, not in a confusing spreadsheet.
• DIRECTOR'S VIEWFINDER / STORYBOARDS - Bring in lens-accurate camera angles via the integrated Director's Viewfinder or Storyboard Import.
• MAC/PC DESKTOP VERSION - An identical Mac/PC Desktop Version is included with the Pro Version (in-app upgrade).
• SYNC & TEAM SHARING - Sync your scenes across all your devices. Share scene folders with teams. Control who owns which scene. (Pro Feature)
Watch the feature-demo at https://www.hollywoodcamerawork.com/shot-designer-videos.html
CAMERA-BLOCKING ON STEROIDS
Shot Designer was developed by Per Holmes, the creator of the renowned Hollywood Camera Work training, and has been developed in conjunction with major TV and Film productions.
Shot Designer is based on the realization that neither Camera Diagrams, Shot Lists, or Storyboards by themselves give you a satisfying understanding of camera-blocking -- you have to use them *together*.
Shot Designer is FAST. The app knows how Directing works and automatically does most of the work for you. Cameras rearrange themselves when you move characters. Animate characters and cameras with simple Walk To and Track To commands. Create sophisticated tracking shots with multiple marks. Shot Designer is fast enough that you can rearrange the diagram with actors waiting.
• Integrated Set Designer for building floor plans.
• Integrated Lighting Designer for DPs, with lighting symbols provided by Ari Golan of Atomic Imaging Studios Chicago.
• Import production drawings as backgrounds and block on top of them.
• Factory Templates of pre-made camera setups for any situation.
• Make your own templates as starting points for new scenes.
• Large and growing prop/furniture library. Email us requests, we'll build them.
• Scene Freeze: Experiment easily by taking snapshots you can return to (Pro).
• PDF/JPG/Excel export and emailing of Camera Diagrams and Shot Lists (Pro).
• Unlimited Folder Structure for organizing scenes (Pro).
The Free Version of Shot Designer is full-featured except for Save, Export and Sync/Team. Your current scene is always saved, and you can be fully productive working on one scene at a time. The Pro Version (in-app upgrade) adds File Management, identical Mac/PC Desktop Version, Sync and Team Sharing, PDF/JPG/Excel Export and more.