Best Solution For Very Large Green Screen in a Sound Stage

[Michael Carter]

Many of the cycs I've worked on are made from the back-side of linoleum, as it can be curved nicely.

One problem with fabric - shooting on a RED or doing high-end film scans, seems like you can key anything. With a more "average" 1080 camera, wrinkles really need to be fought with. Fabric panels need a way to tighten the fabric as it's steamed if you want 'em perfectly flat. After shooting a lot of greenscreen this year, I'd much prefer hard painted set walls. Seamless chroma paper is nice, but the color is a little dull in my experience.

Good luck with your facility though - sounds awesome!

[NBside]

Hey Michael, thanks a lot!

Ive actually been doing a ton of Google'ing and have come across many methods of building rather affordable cyc walls. From what I have seen, masonite appears to be the preferred material, however linoleum is a great suggestion as well. Just out of curiosity...considering this is a green screen cyc, and not the traditional white cyc, I wonder how important the typical "curve" factor is. Im curious if just building a standard straight wall, and then a flat floor that meets at the bottom, would be adequate. Then, I could figure a way to build a smaller curve to connect the two if need be. The only reason I say this, is because this appears to be the most complicated and expense portion of the build. Granted, I dont have any plans on skimping anywhere on this project, but that was just a random thought.

I agree with the fabric point, too. I shoot mostly on DSLR's right now, and wrinkles in fabric are one of my greatest headaches. I pretty much have to de-wrinkle after every couple of shoots. I thought about even building hard walls for my portable screens, and just putting them on frames with casters on the bottoms. I havent used the chroma paper yet, though I have used neon green poster boards before when shooting some car scenes and didnt have my full sized screen handy. It worked, but isnt something Id like to do if I dont have to.

Thanks again for the reply!

[Doc Bernard]

For future readers of this thread.........someone should chime in and describe what a CYC is. They can be built very small scale (I built a 4' wide one for product photos) and larger than 20' wide.

But I will let you guys describe it and why they can be an invaluable VFX/Film tool.

NBside, the curve is crucial to a CYC. when you don't have one, it's not a CYC. The curve is there to eliminate the horizon line and blend the color between the horizontal and vertical planes.

Without the curve, then it just a room painted or backdropped with Chroma color.

[Michael Carter]

The curve - for greenscreen - would be pretty nice; it's much harder to get an even green in a hard corner (done it before) and then you will always have a hard floor line to rotoscope out.

[NBside]

@Doc... You're correct. The curve is what makes a Cyc a Cyc. I should probably have explained myself better when stating my question. What I really meant to say was, Im curious if just building a flat green wall and floor would be as effective. Not only for the fact of having to build the perfect curve, but mostly, for the fact that if I needed the space for something else, I could just cover up the floor...or build one thats can come apart rather easily, so I can use all of the space for set construction. Re-reading my post, I guess I really didnt detail that well enough. My apologies.

I am, however, still leaning more towards the thought of building a cyc...even if I have to scale down my initial plan for size, I think it will be most adventageous. That, and several moveable fabric screens or walls.

@Michael...You're right about the hard corners, too. That why I was thinking, that even if I did just build a flat wall and floor, that I would stretch fabric over the corners to simulate the curve. Like I said, mu biggest concern was the ability to use as much of the space for every facet of production possible. I didnt want to limit my set construction area, for productions that dont require the green screen. However, Im going to have to bite the bullet and decide which is most important and do it right.

[NBside]

Oh.. and for future readers.

A "Cyc" or "Cyclorama" is a background wall constructed of curved surfaces to create the illusion of no perceived end or beginning, and eliminates a horizon line. This makes it impossible to differentiate between where the floor ends and the wall begins. Some cycloramas also incorporate a curve at the top, to prevent distinguishing where the wall ends and ceiling begins. Cycloramas can be done in any color, and not used solely for the purposes of green screens, to create an infinite background. Commonly, cycloramas for film purposes are generally "chroma-key green" or white, however, it is possible to create the illusion with any color. A lot of people compare a cyclorama to be like being inside of a giant egg.

The below image is an example of a chroma-key cyclorama.

page13_2.jpg

**image borrowed from digitalfilmstudios.com**


-I hope my definition was descriptive enough...perhaps someone can add to my explanation-

[NBside]

I should also note, that a cyclorama can consist of as many walls as the builder sees fit. From one flat wall with a curve connecting to the floor, to two walls, like the image at the bottom of my previous post, to 3 or 4 walls. Also, as Doc mentioned, they can be built in a wide range of sizes. From a few feet in width, to some of the larger 100+ feet walls used in major film studios. The design and size is all up to the builder and what meets their desired needs.

[NBside]

I just posted another thread about the studio complex as a whole...I accidentally posted in the wrong section, but heres the link if anyones interested. It's a very exciting project that Im very pleased has started to come to fruition.

http://www.dvxuser.com/V6/showthread...n-Eastern-Ohio

[dwiener]

You might check out a vendor like Rosebrand. They sell keying fabrics and could probably sew up any size you need