sample of green screen made easy

GREENSCREEN MADE EASYKEYING AND COMPOSITING FOR INDIE FILMMAKERS

BYJEREMY HANKE & MICHELE YAMAZAKI

PUBLICATION DATE: APRIL 20099781932907544

PUBLISHED BY MICHAEL WIESE PRODUCTIONSDISTRIBUTED BY INGRAM PUBLISHER SERVICES

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T A B L E O F C O N T E N T S

CHAPTER 1: WHAT IS CHROMAKEYING?Basic conceptsColor spaceCompression limitations

CHAPTER 2: TO BUY OR TO BUILD A GREENSCREENMain Uses Help You DecideAdvantages/Disadvantages

CHAPTER 3: POPULAR OPTIONS FOR PURCHASING A GREENSCREEN

The rolled cloth backdrop and standPortable FlexScreensCutting Edge - Chromatte

CHAPTER 4: BUILDING YOUR OWN GREENSCREENSCreating Greenscreens with rolled paperPainted Greenscreens using walls, flats, and foam coreCreating and hanging your own cloth backdropsThe portable, vinyl greenscreenCombining elements to create a cyclorama greenscreen studio

CHAPTER 5: GETTING YOUR BACKGROUND ENVIRONMENTSPhotography & VideographyDigital Matte Paintings3D RenderingMulti-layered compositesPublic DomainInternet & NegotiationStock Backgrounds

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G R E E N S C R E E N M A D E Y A M A Z A K I

CHAPTER 6: LIGHTING YOUR MATTE FOR MAXIMUM KEYING SIMPLICITY

Positioning Your Lights EffectivelyTypes of LightingAdditional lighting elements to make your colors “pop”

CHAPTER 7: LIGHTING AND POSITIONING YOUR TALENT FOR OPTIMAL BLENDING

Preplanning the lighting to blend between foreground and background planes

Different types of lighting for your foregroundPlacement of the actor and other blocking considerationsTricks to popping your talent from the background

CHAPTER 8: CAMERA TECHNIQUES FOR CLEAN KEYSOptimal distance and behavior of cameraSetting Up Your Camera for Great KeysCreating High Definition footage with a Standard Definition camera

CHAPTER 9: PRODUCTION IDEAS FOR CREATIVE GREENSCREEN USES

The Invisible Man/Dancing ClothesSin City MakeupLuma KeyingShooting Flame or SmokeStop Motion Animation

CHAPTER 10: PRODUCTION RULES TO SHOOT BY16 Rules to Shoot by5 Things To Prep Your Talent With For Optimal Shoots

CHAPTER 11: PREPARING THE FOOTAGE - MICHELE- Deinterlacing - third party solutions- Denoising and deartifacting - third party solutions

CHAPTER 12: KEYING ESSENTIALS Great Keying Technique vs. Good Storytelling

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CHAPTER 13: PREPARE YOUR FOOTAGECheck Pixel Aspect Ratio/Frame Aspect RatioDeinterlace your fields - Deinterlacing in After Effects - Third Party Solutions for Dealing with FieldsDe-noise and De-artifact - Reducing Noise per Channel - The Remove Grain Filter in After Effects - Open a Second Comp Viewer for Better Monitoring - Third Party Solutions Reducing NoiseCheck your Edges - Smoothing Edges with Channel Combiner and Channel Blur in After

Effects - Third Party Solutions for Smoothing Jaggy Edges Even Out Your Greenscreen - Third Party Solutions for Evening Out Your GreenscreenSave an Animation Preset of your Pre-Process EffectsGarbage Mattes (aka Junk Mattes) - Making Garbage Mattes in After Effects - The Bi-section Method - Making Garbage Mattes in Final Cut Pro - Third Party Options for Garbage Matte Creation in Apple Final Cut

Pro - Making Garbage Mattes in Motion

CHAPTER 14: GETTING TO KNOW THE KEYERSAn Overview of some Keying Plug-ins in After Effects - Your Basic Color Key - Color Difference Keyer - Luma Key - Inner/Outer Keys

CHAPTER 15: AN OVERVIEW OF SOME THIRD PARTY PLUG-INS KEYING PLUG-INS FOR AFTER EFFECTS, FINAL CUT PRO AND MOTION

The Foundry Keylight Red Giant Software Primatte Keyer ProOak Street Software VKey2 - Useful Shortcuts for Working with Channels in Apple Motion:Digital Film Tools zMatte

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CHAPTER 16: MASTERING THE ART OF KEYINGAharon Rabinowitz’s Super Tight Junk MattesMultiple Edge Masks - The Multiple Edge Mask Technique in After Effects - Automatically Cycle Mask Colors in After EffectsColor Correction - Color Correction in Final Cut Pro - Third Party Options for Color Correction

CHAPTER 17: FIXING PROBLEMS Hair and fur and other tough to key edges - Matte Tools - Third Party Matte ToolsRemoving Tracking DotsSpill and Despill - Spill Supression In Adobe After Effects - Third Party Options for Spill SupressionKeying Motion Blurred Footage - Third Party Options for Keying Motion Blurred Footage

CHAPTER 18: MAKING YOUR COMPOSITE LOOK BELIEVABLEMatching Grain - Match Grain in Adobe After EffectsLight WrapLight AngleDepth of FieldReintroducing ReflectionsCreating Shadows - Third Party Solutions for Projecting ShadowsAdding Motion Blur back into the Video

CHAPTER 19: COOL TRICKS AND INSPIRATIONDancing Clothes aka The Invisible ManRed Lips, Gray FaceKey Smoke and Fire? Not! or How to remove a black background from

fire, explosions, smoke, window cracks, etc.Replace Television or Computer Screens

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CHAPTER 20: COMPOSITING 3D WITH GREENSCREEN FOOTAGE

Choosing a 3D software that meets your needsCreating 3D backgrounds in 3D software.Rendering your backgrounds correctly3D Channel Effects in After Effects - Depth Matte Effect: Placing your Greenscreen Shot within your 3D - Depth of Field with .rpf filesMatching your 3D and Footage

CHAPTER 21: THE FUTURE OF LOW BUDGET KEYINGJeremy’s Look at the Production End of Things

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CHAPTER 1: WHAT IS CHROMAKEYING?

I f you’re reading this book, you probably have been fascinated by the effects work you’ve seen in Hollywood films, in everything from The Matrix to the Lord of the Rings to Sin City. All of these

films use chromakeying to allow some element of the storytelling process that the filmmaker wanted to show but could not be shot in a normal, real-world environment. To be able to magically place your actors into steaming jungles, science fiction metropolises, or ultra-gritty city streets has been a pursuit of filmmakers since Florey and Vorkapich’s The Life and Death of 9413 – A Hollywood Extra and Fritz Lang’s Metropolis experimented with stationary mattes. These early filmmakers used cut mattes to block a sec-tion of the exposure of the film negative and then used reversals of these mattes to expose only these sections to alternate scenes. Because these early effects combined portions of two scenes, they were the first composites. Later, motion mattes were utilized during the filming of movies like Mary Poppins, which allowed a background to be removed from behind a moving actor. These motion mattes were actually the first form of chromakeying.

So what exactly is chromakeying? Many of us find the term “chroma-keying” to be a bit daunting. Even the name is a little confusing, as it sounds like something you pay to have done to a classic ‘57 Chevy’s bumpers. Of


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course, it becomes at least a little more familiar to us when it’s boiled down to its most popular derivative in this neo-digital age: “greenscreening.”

I’ve done a lot of research into this subject as I’ve prepared for this book, but I’m hard pressed to give a more concise description of the tech-nology than the one that effects filmmaker Zach from Fox’s On the Lot put it: “greenscreening is just basically telling the camera to replace anything it sees as green with whatever you [the director] want.”

So where exactly does the term “chromakeying” come from? “Chroma” is the word used to describe color that a camera can record in technical terms. (As opposed to “Luma”, which is the word used to describe the light that a camera can record.) “Keying” is an old production term that refers to removing an object from a picture using a form of matte. So chromakey-ing is simply removing any color that you designate and creating a matte in the shape of the removed color. (This is especially appropriate because chromakeying didn’t start out with the color green, or even the second most popular color – blue – for that matter. Mary Poppins utilized a yellow background behind the actors.) Over these matted out areas, the keying or editing software you use shows any background you choose.

(Because of the prevalence of the term “chromakeying” in the televi-sion industry (whereas we are writing a book about filmmaking), we will stop using that term and simply refer to this concept as “greenscreening”, to prevent confusion.)

Just because we know the general science behind greenscreen technol-ogy, however, doesn’t make the creation of truly convincing greenscreen effects any less mysterious. After all, it’s all well and good to realize that you shoot something or someone in front of a colored background that is dif-ferent than your subject and you can have almost any editor or keyer delete the background. However, anyone who’s dabbled in this strangely occult field has probably discovered that their results often don’t hold a candle to the work done by ILM or TroubleMaker Studios.

When you try greenscreening and don’t get great results, it can be really tempting to just write it off as something that’s not able to be done in a believable way on a low budget. Hollywood has extremely powerful equip-ment, software, and a lot of money to make its movie magic, so it can be easy to believe that their advantage allows them to do what we cannot. As we were preparing for this book, we looked at the most common hurdles to low- budget filmmakers being able to get good quality greenscreen results.

W H A T I S C H R O M A K E Y I N G ?

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The number one hurdle was simply a lack of readily available infor-mation on the art of greenscreening. Aside from some work that Creative Cow and Andrew Kramer had done, up until the past year information has been very minimal on the art of greenscreening for the low-budget filmmaker. As such, lots of filmmakers just had to strike out on their own and try to get something that looked halfway decent, hoping they would happen upon the right blend of color, lighting, camera quality, and keying software to get what they were aiming for. While some folks have suc-ceeded in this area through self teaching, many more have given up after being unable to harness this technology. This past year, more magazines have looked at greenscreening and at least one additional book on the art of greenscreening has now been released. However, most of these resources had a greater focus on surrealistic greenscreening as opposed to realistic greenscreening. The art of greenscreening a weathercaster or someone in front of digital background for an infomercial is not the same art as the art of greenscreening a protagonist into a 3D temple and making it believ-able. In the weather and infomercials, everyone knows it’s all computer generated and they don’t care. But, in feature films, you’ve got to con-vince the audience that your actor is really in the location you’re showing. Low-budget feature film greenscreen is the most profound magic show on the planet, because you have to be more deft with sleight-of-hand than Hollywood does, because you just don’t have the budget to do things the way Hollywood does them.

Going on from here, this opening chapter is designed to give you some understanding of how to recognize the limitations low-budget filmmakers have in regards to their equipment, because only by understanding your limitations can you understand how to overcome them.

To explain why many of us have had frustrating results when it comes to greenscreening, we must start with the fact that we have been working with sub-optimal source material.

What do I mean by sub-optimal? DV, HDV, and even most HD foot-age is sub-optimal. This is due to how DV, HDV, and HD cameras that are affordable record light (luma) and color (chroma) information. (The only exception to this is the new Red camera, which is only affordable because Jim Jannard, the president of Red, is already the multi-millionaire owner of Oakley Sunglasses and doesn’t mind creating a Hollywood-quality digital camera for about 10%-15% of the cost of competing cameras. The $30,000


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startup price is still outside most of our reader’s pocketbooks, but it’s a massive stride in the right direction compared to its $250,000-$300,000 competitors.)

Color information takes up a lot of bandwidth, but is not as noticeable to the human eye as light data is. As such, when DV camera manufacturers were playing lifeboat with different pieces of information for the record-ing and compression codecs used in these cameras, they decided to record

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every pixel of light their cameras sensors picked up, but only one out of four pixels recorded color data for NTSC DV cameras.

This was called “4:1:1” color space, with the “4” denoting that four out of four pixels light information would be recorded, the first “1” denoting that one out of four pixels would have color information recorded in the first line, the last “1” denoting that one out of four pixels would have color information recorded in the second line. From here, it is compressed, but, luckily, each frame is compressed separately.

PAL DV cameras (and now HDV cameras) record with a 4:2:0 color space, which, again, records four out of four light pixels, but records color information on two out of four pixels of the first line, and NO color infor-mation on the second line. PAL DV compresses each frame separately, just like NTSC DV.

However, in order for HDV to fit on a single tape, multiple frames must be grouped together and compressed in clusters of between 7 and 15 frames. (7 for JVC and 15 for Sony.) Obviously, when you mash groups of frames together and then must untangle them before you can even begin to key them, this makes getting good keys harder.

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HD cameras include everything from Panasonic’s HVX200A all the way to compressed Viper footage, and they have a 4:2:2 color space. Again, four out of four pixels have their light data recorded, while every other pixel has its color data recorded in both the first and second line. Again the footage is compressed before being recorded to the hard drive or tape, but like DV, each frame is compressed individually, which means that there is less damage done by the compression.

So what’s the color space in those high-end cameras that Robert Rodriguez used to shoot Sin City? Uncompressed 4:4:4. That means that every pixel is recorded for both light and color and recorded without com-pression to a RAID array. Obviously, this gives you optimal chromakeying latitude, as the keying program isn’t trying to guess where pixels are due to insufficient color information. (The aforementioned Red camera generates this same color space provided its uncompressed Redcode RAW stream is recorded.)

For most of us, 4:4:4 is not something we will likely have access to until the Red drops further in price, we sell one of our films for a sub-stantial profit, or we try to hijack the signal from our cameras before its color information gets decimated. (Believe it or not, a company called Real-Stream has a $2,500 adapter which they will install in a DVX100 or HVX200A camera so that you can download uncompressed 4:4:4 data directly from the camera’s imagers. Unfortunately, the program that

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reads this data stream is only available for Macs and, reportedly, extremely unwieldy to use. Hopefully, in the future, they will come with a cross-platform package that has the kinks worked out.)

Obviously, I don’t tell you all these things about greenscreen tech-nology to make you feel like you have to save up until you have a 4:4:4 uncompressed camera in order to start learning it. Instead, I tell you these things so that you understand why special work needs to be taken to get the best keys out of lower end cameras. From that perspective, in this book, we will discuss how to either purchase or build the best type of greenscreen for your needs, then we will look at how to light both it and your actors properly, how to shoot it cleanly, how to key it with one of the programs that works well with DV/HDV/HD footage, and, finally, how to composite your keyed footage with both real and 3D generated elements.

Buckle up, because this is going to be a wild ride.

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CHAPTER 2: TO BUY OR TO BUILD A GREENSCREEN

Okay, to briefly recap the ending of last chapter, we assume that one of your grandparents hasn’t recently left you a large inheritance to purchase one of Robert Rodriguez’ cameras

nor even a medium-sized inheritance to purchase a new Red One. As such, this means that you’ll likely be doing your shooting with a 4:1:1 camera like the Panasonic DVX100, 4:2:0 camera like the Sony HVR-Z1U, or a 4:2:2 camera like the Panasonic HVX200A.

With that in mind, how do you get started on the right foot to make sure you get clean keys in post?

To help insure the best possible success, it is imperative to start with the best possible greenscreen you can either afford or construct. Once you have it, of course, you’ll want to light it, position it, and treat it properly, but we’ll cover those facets in future chapters.

Now, before we go into whether to buy or to build a greenscreen, the question invariably pops up: should it be, in fact, a green screen, or, instead, should it be a blue screen? As the terms appear to be practically interchangeable in every DVD extra you watch – and even in many spe-cial effects books – it’s hard to keep track of who uses which color for what purposes. Even professionals seem to get glib on this subject. To illus-trate what I mean, one of our staff writers was on an industry tour of a Hollywood studio and one of the other people in the group asked the guide what the difference between greenscreen and bluescreen really was.

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The guide snidely responded that, “Well sir, bluescreens are blue and green-screens are green.”

So, what is the difference, then? Well, the choice of color is based on two factors: the color of the clothing, hair, or eyes of the person being recorded and the medium that is doing the recording.

Obviously, if the talent has blue clothing, the green screen is the cor-rect choice, whereas if the talent has green clothing, then the blue screen is the correct choice. However, much less obviously, the color of hair has a direct bearing on the screen choice. (And no, we’re not talking about our friendly neighborhood punks who have literally dyed their hair blue or green.) Blonde hair has a way of picking up green that makes it very dif-ficult to key properly from a greenscreen, which is why it’s customary to always film blondes in front of blue screens. Now, if your actors have non-blonde hair and are wearing neither blue nor green, you will normally look to what you’re recording on. Film’s blue latitude is excellent, which is why it was the most intelligent choice for people recording to film. However, with the use of digital recording, more green data is recorded (especially in lower-priced cameras like the ones you’re using, which discard more infor-mation from the red and blue channels). This means that, for most of our readers, greenscreen is often the best choice.

Now with that said, this doesn’t mean that the bluescreen concept gets thrown out entirely for digital filmmakers, even if you’re not shooting blondes or actors with green clothes (or bright green eyes) in your film. Digital video cameras can still get a very useable key from bluescreens and it is actually easier to make the color blue really pop (which tends to make it more distinct from your foreground subject and, therefore, easier to key) with inexpensive lights. And, of course, for films that are going to have a stylistic blue-tinted final color pass or that are using water and/or cloud-based effects, it’s better to use blue. (For example, Evan Almighty, which includes massive flood effects, utilized bluescreens to good effect because of the blue coloration of the water.) As an added benefit to blue screen, if you end up with some spill (color reflected onto your actor from the background) that can’t be removed in post, blue is less noticeable to the human eye than green is. As such, you should at least play around a bit with bluescreen and see if it does what you need for your film.

Since green is still going to be the color that’s going to work for many of our readers most of the time, for simplicity, we will simply refer to all


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color-keying technology as “greenscreen” unless we are actually referring to a literal blue screen.

So, now we get into the question of whether you should purchase or build your greenscreen. While there is usually no one “right” answer for this, there are some clues that can help you decide.

The first clue is what you’re going to be using greenscreen technol-ogy for. For example, are you going to be using it to delete a few buildings, trucks, or light poles from an otherwise useable shot? Or, on the other hand, are you going to be using it to completely get rid of all naturally occurring landscape? If it’s the former, you’re normally going to want to buy a col-lapsible greenscreen, because, as the name implies, collapsible greenscreens are designed to be taken down and put up quickly and with minimal hassle, which makes it ideal for removing a few background things, but leaving the rest of the environment intact. (A great example of this sort of work would be the Lord of the Rings trilogy, where sky and other elements were covered up with portable greenscreens, while the rest of the environment was filmed as is.) However, if you’re wanting to completely remove all nat-ural elements, you’re probably going to need to build a greenscreen studio of some sort. While there are some companies that will build professional greenscreen studios for you, the cost of one is easily going to be outside the price range of our readers. As such, that means you’ll have to put in the elbow grease yourself, but, when you’re done, you’ll be able to place your actors in virtually any environment, from outer space to Discworld and everywhere in between. (A great example of this sort of work would be Robert Rodriguez’ Sin City.)

A second clue is whether you want greenscreen to be a small part of one film or a continuing part of your filmmaking repertoire. If it’s to be a smaller part, then a purchased, collapsible greenscreen would be a great choice. It’s not terribly expensive, it can be used from time to time, and it doesn’t take up much space when you don’t need it. If it’s to be a larger part, then building a greenscreen studio is your best bet. (Of course, if you’re going to do greenscreen a lot, having both would be an excel-lent choice.)

These clues can give you a rule of thumb as to your greenscreen needs. However, you can also creatively change this up if you so desire. For example, a few purchased portable greenscreens can be patched together to create a greenscreen studio, while a hand-made, foam-and-paint portable

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greenscreen can serve to remove unneeded background segments. (In fact, the movie Dirty Trousers, which we will reference at various times through-out this book, used a number of these makeshift greenscreens to remove intrusive areas of reality.)

With that said, let’s get into the options for both purchased and built greenscreen setups.

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CHAPTER 3: POPULAR OPTIONS FOR PURCHASING A

GREENSCREEN

I f you can afford them and they suit your needs, buying green-screens is usually your best bet, because their coloration has been professionally treated and is designed to make it easier to get a uni-

form key off of them. If you find a few different manufacturers who offer slightly different shades of green (or blue, if you want a bluescreen), you’ll often want to get a darker shade. The reason for this is that it’s easier to overlight a greenscreen than many people think. If you overlight a lighter color of green, you will actually wash out the green color and, therefore, make it harder to key. As such, a darker shade of green is going to give you more latitude before you start washing out the green color, which should make your keying endeavor easier.

With that said there, let’s look at a number of options available to us.

3a. The rolled cloth backdrop and standThe rolled cloth and stand can be a great fit for many low-budget filmmak-ers, because it’s fairly portable and can usually be rolled out to go under the actors’ feet, thus providing a cyclorama effect. (More on this will be covered in our next chapter, but the cyclorama effect is achieved by having a curving wall of green that goes from the wall of the greenscreen to the floor so that there are no hard edges for shadows to get caught in, which are very hard to key properly.) A number of different manufacturers make

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them from lower budget companies like ImageWest and effects companies like Elsdon Enterprises FX (EEFX) to Rosco – the industry standard in gels, filters, and greenscreen backgrounds —with their DigiComp line of cloth. (The DigiComp line also extends into paint and tape, the latter of which can be used to connect cloth or foam screens and to create tracking marks for moving shots.)

Now, although most of our readers are going to be inclined to look for the least expensive roll of greenscreen cloth they can find, it’s important to think of the thickness of the cloth. By and large, you want to get thick cloth because it can hold a deeper green color without being washed out, is much less likely to keep getting wrinkled, and is also less likely to tear. There are some companies that make backdrops out of muslin, which, in my experience, is far too thin and wrinkly to do a decent job.

Rosco’s material is pretty heavy duty but doesn’t have special backing, which means it’s not completely wrinkle free, but it does match perfectly with all the other products in Rosco’s DigiComp color line, including tape and paint. A bolt of cloth about 5’ x 30’ runs $110-$120 while a bolt that’s 5’ x 60’ will run you $220-$230. (You will need to sew rod pockets into the cloth yourself, if you want to hang these from a rod.) DigiComp tape to cover seams or hold fabric in place will run you about $23-$25 for a roll that’s 2 inches wide x 55 yards long.

EEFX creates a special greenscreen fabric that’s !” thick, and is com-prised of a light diffusing green fabric, foam core behind that (so it won’t wrinkle), and nylon backing behind that (so it won’t tear). They sell seam-less rolls of this fabric (measuring 5’ x 12’) for about $70-$80 and will stitch together rolls all the way up to a 20’ x 30’ size for a medium cyclo-rama studio for less than $900. (They will also sew rod pockets to hang the fabric for an additional $15 - $50, depending on how large the fabric you buy is.)

3b. Portable FlexscreensThis is probably the answer that most filmmakers who do not need to shoot full-length body shots will go with. These screens are designed to pop open from a collapsed state, much like Photoflex reflector screens or those pop-out tents that are popular for camping. While these are often a huge pain to re-collapse, their overall convenience is extremely high. They can be stored almost anywhere, they tend to have heavier material than


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most cloth rolls, their framework stretches the fabric tight so that there are very few wrinkles, and most screens are green on one side and blue on the other, which allows you to do use one screen for both greenscreen and bluescreen work. These can be bought for $60-$400 from ImageWest, Lastolite, Photoflex, and Westcott.

As useful as these flexscreens are, many of them have an Achilles’ heel: a black border. Why anyone would ever have created a greenscreen with a black border is beyond understanding, as any shots that show the entire screen must have the black frame rotoscoped out. If you need to show the edges of your screen in your shot, Westcott appears to be the only manu-facturer that makes a collapsible greenscreen with a green border. (Their 6’ x 7’ reversible screens with stand run about $300.)

3c. Cutting Edge - ChromatteChromatte is a technology made by Reflecmedia that makes greenscreen compositing much easier. It’s a special lighting/backing package that includes a special, heavy-duty fabric coated with tiny glass reflectors and a special LED LiteRing that goes around your camera’s lens. The Chromatte

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fabric looks grey under normal light, but is created to specially reflect the light emitted by the LiteRing, which can be purchased in either blue or green for about $600 and includes a dimmer. The Chromatte fabric comes in either drapes for studios or pop-out screens for on location work. It’s hung behind the talent in any way you desire and then you light your sub-ject normally. Once you’ve lit the subject correctly, the LiteRing is switched on and adjusted via the dimmer until the background glows with a per-fectly even blue or green color. (Because of the way LiteRing is designed, it doesn’t cast a blue or green hue on your actors.) Since special lighting doesn’t have to be applied to the background screen, Chromatte setups require fewer lights and tend to key very cleanly.

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However, there are some problems with this revolutionary form of chromakeying. First off, while the long-lasting LED LiteRings are reason-able at $600 per blue or green ring, the fabric is very pricey. At $32 a square foot, it’ll run you about $19,200 for a 30’ x 20’ drape for a mid-sized cycolorama. (If you want a smaller setup, which can be doable since you don’t have to worry about spill nearly as much with the Chromatte system, you can get a 7’ x 7’ drape with LiteRing for about $2,000.)

Secondly, even though the LiteRing doesn’t cast a hue on your actors, its highlight is reflected in certain types of wet and/or highly reflective surfaces. While avoiding reflective surfaces is something you tend to do in any form of greenscreening, it’s impossible to do in close ups and extreme close ups when the wet, reflective surface in question is the human eye. Rings of green or blue highlight show up in the irises of actors’ eyes in these type of Chromatte shots, which you will either have to rotoscope out via moving “red eye” (or rather, “green eye”) reduction or track the appro-priate color behind the eyes themselves to make these shots useable. The only way to avoid this is to very carefully choose your camera angle, zoom depth, and LiteRing dimmer levels to minimize or eliminate the likelihood of it showing up.

Despite this last setback, when the price on this setup drops (or a competitor releases a lower priced alternative), it will definitely be worth looking at to add to your greenscreen arsenal, because of the comparative simplicity of lighting and the ease of keying.

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CHAPTER 4: BUILDING YOUR OWN GREENSCREENS

Now that you’ve looked at buying some of the pre-built green-screen options, many of you would like to know about how you can build your own greenscreen options. While many of

these will relate to more permanent setups involving painted walls, cloth backdrops, and a full studio, we also have included some more portable options, like foam core boards and the portable vinyl greenscreen.

While we discuss mainly home-built/mixed options here, we will cover some of the readily purchasable providers of things like paint, tape, and cyclo-rama panels, as there are some advantages to go with professional supplies.

4a. Creating Greenscreens with rolled paperLots of art supply stores will sell wide rolls of green paper, ranging from 3’ – 8’ wide. (These can be found for as little as $25-$30 for a roll 4’ x 200’) With a little work, you can build a stand that holds the paper on a spool and pull it down behind your actors, much like a photographer uses rolled backdrops to pull down behind his/her subjects. Because of the length of these rolls, you can pull them down to the ground so that the actor can stand on them and be able to be shot at full body length. While the rolls of paper can be fairly narrow, it’s not a problem so long as your talent’s hands or body don’t move past the edges of the greenscreen. (Of course if you’re creating HD footage with an SD camera, you already have this mindset down to a science. [Shooting HD footage with an SD camera is fully described in Chapter 7, section c.])

In addition to the traditional roll setup, you can tear sheets of this paper and tape it to walls with colored painters’ tape or Rosco’s DigiComp tape to create a larger greenscreen.


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4b. Painted

Greenscreens using walls, flats, and foam coreObviously, if you use paint, you’re more likely to working on something that’s designed to be permanent, like walls or a cyclorama. Of course this isn’t always the case, as some creative uses of paint can be used for more temporary options, such as flats or foam core. Flats are most often large pieces of canvas built into rugged wooden frames and are great for a mov-able studio scenario, as this can allow you to put your greenscreens in more 3D layouts. Foam core is fairly cheap and light, so it can be used to create truly portable solutions. Unfortunately, it’s also pretty easy to ding up, so you’ll want to make sure you always have paint handy for touch ups on location.

Now, you can buy professionally-made chromakey paint or you can make your own. While there are many manufacturers of greenscreens, there aren’t very many makers of greenscreen or bluescreen paint. EEFX makes some pretty good stuff, while a lot of professionals use Rosco. For EEFX paint, you’re looking at about $50 a gallon whereas Rosco’s runs between $75-$110 per gallon. Both manufacturers have made their paint match their fabric lines, but according to the folks at Rosco, their paint is formulated to require only one coat, which should mean that, in theory, you could cover twice the surface area with it as you can with a gallon of the EEFX paint. As EEFX states that you can cover 250-350 square feet per gallon of their paint, we would presume the Rosco paint would double that. However, Rosco doesn’t publish coverage statistics, so that can’t be confirmed.

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If you would prefer to make it yourself, Tom Stern, one of our staff writers at MicroFilmmaker Magazine, went through the arduous process of calibrating his camera to color swatches he found at Lowe’s and then painstakingly sampling each color in Photoshop to see which generated the most pure green and the least gray. At the end of his testing, the mix he came up with that yielded the most green was a matte-finished latex house paint made by Olympic/CCA called “Botanical Green.” A gallon of this will run you between $10-$15, if you’re reading this book in the next year or so. (All prices will be substantially more if you waited until 2020 to pick the book up used!) Make sure to remember that you’ll normally need to put two coats of paint on to get a good, even finish.

4c. Creating and hanging your own cloth backdrops

Rummage through your local cloth purveyor’s stores and see if you can find cloth that’s a true green, that’s pretty heavy, and not too shiny. (Feel free to take a swatch of the Botanical Green color we mentioned from your local hardware store to test cloth colors against it.) You want to avoid fabrics with designs stitched into them and ones that are textured, like velvet. Once you’ve found a good fabric –probably a good heavy-thread count broadcloth or muslin—get as much of it as you would anticipate needing. (Remember that you’ll probably be having your actors stand 6’ – 10’ away from the background cloth, so you’ll need enough to stretch that far.) Once you purchase your fabric, see if they will staple it to an extra fabric tube they have lying around in back and roll it on for you. (The heavy duty cardboard rollers will make a great spindle for your backdrop and having them staple it will guarantee you won’t unroll too much.) If they won’t, then a heavy duty dowel rod that is about 2’ – 3’ longer than the width of your fabric can be used instead. Just make sure to either staple (or nail) one end of the fabric to the dowel or sew a rod pocket in the top of the fabric that the dowel can go through, so that the fabric can’t come loose at the end.

From here, you simply need to buy or construct some sort of backdrop support for the ends of the dowel or the tube. You can purchase backdrop support kits that are made from aluminum with an aluminum cross bar for $80-$300. To build a very simple setup, you can affix loops of wire or rope to your ceiling or the top of your wall at the same distance apart


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as the dowel or rollers length and hand the rod through the loops. (For smoother rolling, you can put a dowel through the cardboard roller the fabric is attached to create a rotating crossbar.) More advanced setups can be built by creating stands out of dowels that are screwed into wide squares of wood at the base. From here, any form of U-shaped top-piece can serve to hold your dowel or roller. (With a little creativity, a pair of U-hook cross bar holders can be affixed, which run between $10-$20.) Just make sure you use sandbags on the bases of homemade holders like this, so that you don’t have instability issues.

Whatever way you go about to suspend your backdrop rod, you now have a background that can be rolled down and then rolled back up when you’re done shooting.

4d. The portable, vinyl greenscreenIf you don’t want to have to fight with something as fragile as paper, don’t want to try to keep foam from getting beaten up, and have found cloth too difficult to keep wrinkle free, then you can create a portable, roll-up greenscreen that’s pretty durable, virtually wrinkle free, and can be cleaned pretty easily.

What you need to pull this off is some cheap vinyl flooring that you can find at Home Depot, Lowe’s, Eagle’s, and a variety of other home improvement stores for about $40. Sometimes, your local flooring whole-saler will need to get rid of a lot of horrendous looking patterns because they aren’t selling well. Since the back of the flooring is what will be

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painted, it doesn’t matter how obnoxious the front is, so this is a great time to snatch these up.

It needs to be a uniform green color that is as close to what the camera perceives as pure green as possible, as opaque as possible, and heavy enough not to wrinkle or crease.

As these are the necessities for greenscreening, we chatted with a few different greenscreen technicians and came up with a pretty simple how-to guide for building your own portable greenscreen for $60. This is larger than most of the portable screens on the market (as well as being much easier to set up and collapse) and it allows a soft curve to meet the floor so you don’t have harsh shadows (which we’ll go more into depth when we talk about cycloramas in 4e).

Here’s what you’ll need and the approximate costs:

8’ x 12’ roll of vinyl flooring ($40)1. One gallon of matte latex house paint, mixed to the color: Botanical 2. Green ($11)One roller paint brush ($5); I used an extendable one that made it 3. much easier to do this project.One paint pan ($2)4. A roll of large garbage bags ( $2)5. A clean cardboard tube or piece of PVC pipe as thick and long as 6. you can find (Rummage for this item)Some packing or duct tape (you probably have some of this stuff 7. floating around)

You will need to find some place that is large enough to allow you to lay out an 8 ’x 12’ roll of vinyl in order to paint it. If you are in a dry envi-ronment, doing this outside will be fine. If you are in a location with high humidity or inclement weather, then you’ll need to find someplace indoors to lay this out. (This is precisely why the roll of garbage bags is listed. Folks who live in a dry enough environment to do this outside can make this greenscreen for $58!)


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Lay out trash bags as a spill guard below your roll of vinyl.1. Unroll the vinyl so that the backing is face up and the finished2. side is facing the floor.Stir your gallon of paint and pour a decent amount into your paint 3. pan.Evenly paint the backing of your greenscreen with one coat of 4. paint. You’ll probably want to do this in bare feet or booties to keep dirt off the screen.Allow to dry for at least four hours before moving. (Ideally, you 5. don’t want to move this until the second coat has dried, but life is not ideal. After four hours, you can loosely roll the vinyl up, tape the top flap down, and let it dry standing up for another 16-20 hours or so.)Approximately 20-24 hours later, paint a second coat on the screen, 6. being very careful to be as even as possible.Allow second coat to dry for another 20-24 hours.7. After it is completely dry, wrap the greenscreen around a clean 8. length of cardboard tubing or PVC pipe and tape the edge of the vinyl to the roll with packing or duct tape. Don’t try cinch-ing bungee cords around the roll (at least not for the first fourteen days or so), or you can cause the latex paint to adhere to the vinyl flooring. The first time I made one of these screens, I made the mis-take of not using an internal roller and secured the roll closed with

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bungee chords; thus I ended up creating an unroll-able, vinyl-green Tootsie Roll out of the whole thing!

Now you can take it wherever you need it. After it’s completely dry, it’s surprisingly rugged.

In order to rig up a hanging version, you can place reinforced grom-mets into the sides of the greenscreen and then tie it up from rafters or other high-placed tie-down spots. Or you can use flooring staples to staple one edge of the screen to the cardboard roll or PVC pipe you rolled your screen around and hang it through a suspended rod. This will give you the ability to have a window-shade greenscreen, which can be very useful.

4e. Combining elements to create a cyclorama greenscreen studio.

If you plan on doing a lot of intensive greenscreen work, then building a cyclorama greenscreen studio is a really smart idea. As we mentioned in an earlier chapter, a cyclorama is made by having a greenscreen that curves from the wall to the floor so that there are no sharp corners and edges. This

3 wall seemless cyc with 16 feet to the grid. Credits: Director: Tiffany Dang, Company: Artemis Entertainment, Photo by: David Torno, Model: Hope Dang


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allows for more flexibility in your keys and cleaner keys, since sharp edges catch shadows in an unnatural way and show up as dark lines that are dif-ficult to key properly.

To begin with, there is a lot of confusion as to how much space you need for your greenscreen studio. You will want to shoot your actors at least 6’ – 8’ from your greenscreen wall and then you will need your camera to be at least 6’ – 8’ feet from your actors for medium shots. For long shots, you will need to be as much as 12’ – 22’ from the subject, depending on lens and the height of the actor. This means that, for a bare minimum, you need an area with minimally 20 square feet of useable space. Obviously, if you’ve been doing the math, it would be preferable to have an area that’s 30 square feet or larger.

As you can imagine, this means that folks who live in a single room apartment are probably not going to be able to build a greenscreen studio at their residence. (Now, I have seen some innovators who have painted their apartment green and managed to get some fairly decent results, but that’s very difficult.) As such, most of the people who are going to be con-sidering this will likely have a good-size two-car garage, a large room in a Southern-style house, or some sort of rented studio or office space they wish to convert to this. (If none of these apply to you, contact local col-leges and universities, especially community colleges. With the growing popularity of greenscreen work, many colleges want to offer some sort of facility for this for their students and might be willing to let you construct a studio on their property in exchange for them being able to use it with their students. You can often work out a deal where some of their students will intern with your production company to help you build the studio, which is a great way to get free labor and might lead you to some people who want to work on your productions after graduation.)

Once you have the space you need, you are going to want to build a cyclorama setup. As we’ve mentioned before, a cyclorama greenscreen is a greenscreen that utilizes a soft curve that buffers the floor and wall so that there are no hard edges between where the wall ends and the floor begins. Corner edges normally capture weird looking shadows in long shots that are very difficult key out, which is why the cyclorama setup is so useful.

While you could make use of the cloth rolls mentioned earlier, this normally isn’t the best option for a permanent studio for low budget film-makers, because most cloth can wrinkle fairly easily, it gets dirty quicker,


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and it’s hard to join seamlessly with other pieces to make up your back-drop. (I say “most”, because the foam-backed cloth created by EEFX is designed to avoid most of these things and is pretty economical. It’s more expensive than the way we’re about to describe, but a lot easier if you’ve got the funds for it.)

The better way to back a low-budget cyclorama is with five of the portable, vinyl greenscreens we described in 4d. The great thing about this setup is that it’s fairly inexpensive, yet it’s resistant to wrinkling and as easy to clean as your wall. To give you an idea of what you’ll be looking at paying for the largest component of this if you have to pay full retail, it’ll run you about $200 for five rolls of 8’ x 12’ flooring, which is enough to give you a 32’ wide panorama that’s 8’ high and has a cyc-curved floor that extends 3"’ from the wall. In the central area, you’ll have an extended floor 12’ wide and 8’ deep, for an effective long shot stage that extends 11’ from the rear wall. (The following illustration shows this concept for a 24’ Cyclorama. The 32’ one would include four panels on the wall, as opposed to three.)

Affix a bar of a soft, sturdy wood (like pine) about 8’ up the walls you intend to use as your greenscreen walls. Then using a screw about 1” – 1"” longer than the wood bar’s thickness, screw the edges of the vinyl flooring (with the painted side facing out) through the wood bar into the wall studs behind. Be careful to not screw the vinyl in at the very edge, as

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linoleum can tear, so leave an inch or two above your screw to be on the safe side. Once you’ve done this, unroll the vinyl down the wall. It will naturally form a cyclorama curve at the bottom due to its manufacture. Affix the vinyl to the flooring with liquid nails, traditional nails, or screws, making sure to keep the cyc-curve consistent. Proceed with each roll like this, making sure that the rolls’ edges line up with one another. For the final touch, you will unroll the last roll and affix it to the floor in front of the edges of the other rolls. This last roll will provide your extended green-screen stage.

If you would prefer to simply create a painted cyc stage, then you will need to build some sort of curved piece of wood, plastic, or plaster that will buffer the edges of the wall and the floor. Once done, proceed to paint your space with either the homemade paint we discussed in 4b and 4d or with professional paint, like that created by Rosco or EEFX.

sample of green screen made easy

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