EEFX FREQUENTLY ASKED QUESTIONS

How do I clean the backdrops?
Can I walk on the green screen?
How should I light the backdrops?
MiniDV vs Solid State, P2 Memory Card, and Hard Drive cameras. What is Better?
Do the seams cause a problem when color keying?
Do grommets or Rod-Pockets come with the standard orders? Does it cost extra to add extra features?
How much do grommets Cost?
How long will it take for my order to process?
What is your standard shipping carrier?
How is the fabric shipped? Do you fold it?
How should I store my backdrop?
How do I remove wrinkles?
How does foam-backed fabric compare to other fabrics?
What makes a larger Chroma Key backdrop better?
What Color is Better (BLUE or GREEN)?

How do I clean the backdrops?

You can wash this fabric in the washing machine then hanging it up to dry. For larger backdrops (too big for a washing machine), put a little soap on a cotton rag (mild soap or laundry detergent) then run the rag under water to dilute the soap (if the soap is not diluted, it will foam up). Use the rag to spot clean the fabric.  If the spots are bad, you can also use stain remover or spray it down with a water hose. After your done, hang out to dry or use a hair blow-dryer for spot drying. The important thing is to clean away any excess soap and let it dry completely before using. If the backdrop is not dry, dirt might attract to the wet spots. Don't be scared to use lots of soap if necessary but don’t use any chemicals that will harm synthetics (IE: 409, bleach, Tilex, etc).

Can I walk on the green screen?

This fabric is very durable and will not rip or tear when walking on it. The Chroma key fabric is made of very strong nylon/polyester so you won't have problems with it ripping. To give you an idea of how strong it is, we've attached 40lbs of lead weight to a 1/2inch wide strip without it ripping (click here to see image). It is also very difficult to cut. You would need sharp scissors or a matte knife to cut it.  When walking on it, just clean any loose mud or dirt off your shoes.
 

How should I light the backdrops?

Daylight corrected HMI's are wonderful if you can get them. To keep cost down we often use 1k Tungsten hot lights with diffusers or umbrellas instead. They are easier to find and cost less. Most Mini DV cameras as well as any HD camera should have white balance options with a settings for Tungsten. If you are shooting on film, then HMI's would be a lot easier to work with. If you can't get access to HMI's when shooting film, you will need to correct the Tungsten lighting using optical filters. We would recommend consulting your camera DP for more info.

The best way to successfully pull a key is to evenly light the entire backdrop. Try to eliminate any hot spots inside the frame. Light the screen from the sides at 45 degree angles. Place 1-3 lights (w/ diffusers or umbrellas) on each side of the screen. Placing your actor 7ft - 10ft away from the backdrop will eliminate most shadowing problems and also eliminate a lot of the color bleed issues. Keeping the actor this far away also makes it easier to light them separately. The way you light your subject/talent depends a lot on the scene you’re compositing them in. After lighting the talent correctly, we often place a rim light either behind/above or to the side of the screen shinning on to the back. This gives you a good separation line and also helps eliminate color bleed issues.

 

MiniDV vs Solid State, P2 Memory Card, and Hard Drive cameras. What is Better?

MINIDV:
MiniDV should not be confused with an uncompressed format. It is indeed a digital format, but it is compressed the moment you recorded to the tape. The camera records to the tape at a 4:1:1 color space. To keep it simple, for every scanline (720 total NTSC) every group of 4 pixels in a row are sampled down to a single pixel. So basically, the color channel on a MiniDV tape is actually only 180x480 chroma samples and not 720x480. The reason it doesn't looks like this is because the Luminance channel is recorded at the higher sample, which give the eye the illusions of color shift. That is why it is difficult to work with Green Screens on MiniDV. If you've every attempted to color key DV footage, you will see white colored stair step patterns on the edges. This can be minimized significantly by using a good keying package. Some of the better color keying programs have built-in settings to eliminate these artifacts. 

SOLID STATE AND STRAIT TO HARD DRIVE FORMATS:
Some strait to hard drive or memory card cameras (Example: Panasonic’s HVX-200) can record at a 4:2:2 color space (or better). To keep this from being a novel, we won't explain too many details, but basically the color pixel information on the Panasonic memory card camera has twice as many color pixels as a miniDV camera even when recorded at the SD 720x480 TV resolution. This means the stair step patterns are cut down by half compared to a miniDV camera.

HDV format:
HDV cameras are becoming more readily available and extremely cheap. Be warned that all HDV cameras that record to tapes are compressing chroma channels at a 4:2:0 ratios and in turn, your chroma channel on HDV is 1/4th compressed simliar to DV 4:1:1 footage. Really the main difference is the image size, but your stair step problem will be just as bad on HDV footage.

Recommendation:
We recommend a 3CCD professional 4:2:2 (1/2 compressed chroma channel) or a high-end 3CCD 4:4:4 (uncompressed chroma channel) camera format.

Will the seam cause a problem?

The seam is so small it should not effect your color key. For most productions, the camera will also be at least 8 feet away, making it hard to notice the seam. Click here to see a shot that utilizes a seamed backdrop. If you look closely, you'll see the seam next to the actor's elbow. It is not large enough to effect the keying.

Do grommets or Rod-Pockets come with the standard orders? Is there an extra charge for these additional features?

Unless specified otherwise in the title or description of our item/auction, rod pockets or grommets are not included with the standard backdrops and are an additional cost.

How much do grommets cost?

The price varies depending how many edges you want modified and the space you want between each grommet (standard is every 2ft). In order to give an accurate quote, we need to know specifics about what you are looking for. . The edges on grommet orders are normally double tucked (folded over at the edges for reinforcement) and sewn down before grommets are placed. Double tucking the edge takes extra time to manufacture, but makes the edges stronger.  This extra strength insures the grommets won't rip out, especially on larger backdrops.
 

How long will it take for my order to process?

Order manufacturing times changes depending on current demands. The estimated processing and manufacturing times are posted in the shopping cart and order confirmation email. This is generated from an average of our current order processing and is not  a guaranteed a shipment date. In general, the larger customized backdrops tend to have longer processing times. Although faster shipping methods are normally processed first, don't assume your backdrop will arrive in 1 day if you pay for overnight shipping. Manufacturing times also applies to Overnight Air and 2-Day air orders. Expedited processing is sometimes available for a minimal service fee. For more information please call our sale office at (805.462.EEFX).

What is your standard shipping carrier?

Because most of our orders require large boxes, we normally ship via FedEx Ground. Depending on the size and priority of the package or the ship to location, UPS or USPS Air Mail may also be used.

How is the fabric shipped? Will it be folded?

The backdrops are rolled up then folded to fit in an optimally sized box. This saves you money on shipping. We will gladly ship the backdrop rolled instead of folded, but it is considered over sized and can cost 2-3x more to ship. Please contact us directly at sales@eefx.com for info regarding the rolled shipping method.

Are you worried about wrinkling? You should be happy to hear that the foam core of our fabric bounces back amazingly well. For storage, fold the fabric at the seam, then roll up on a pole or on itself. Another option is to loosely fold it up. Remove every month or two and refold differently each time to eliminate any creasing.

How should I store my backdrop?

The best method would be to fold the fabric at the seam, then roll the fabric up on a pole or on itself. Another option is to loosely fold it up. Unroll it  every month or so and refold differently each time to eliminate any creasing. If you keep it folded, once you hang or lay it out, the foam core bounces back amazingly well

How do I remove wrinkles?

Once you hang or lay the fabric out, the foam core bounces back amazingly well. Let it hang up for a day or so, depending on the extent of the wrinkles and the wrinkles should disappear.  If you need them out faster, fill up a spray bottle with water and spray the back side (in the area with wrinkles). The water will speed up the foam expansion process and remove wrinkles within 30-45Min's. Use a hair blow drier if you need to dry the fabric quickly. The foam back fabric is the best in the industry when it comes to wrinkle removal. 

How does foam-backed fabric compare to other fabrics?

Our fabric is used by most visual effects supervisors and is preferred by artists because of many reasons. First of all, it is composed of a three layer laminate design. The layers include a foam core center, nylon mesh backing, and chroma key diffusion face. The nylon backing makes it almost impossible to tear. The foam core gives it the ability to stretch and also bounce back from wrinkles. The chroma key face layer is very strong and is composted of a series of tiny loops that diffuse light for a more evenly exposed backdrop. There is no other fabric like it in the industry.  Although it may cost more to manufacture compared the other single layer woven fabrics, our prices are extremely competitive for quality foam-backed fabric. EEFX.COM is owned by a visual effect artist that has worked on projects ranging from feature films to commercial spots and has used all different types of chroma key fabrics and paints. As most visual effect supervisors will agree, Foam-Backed Fabric is FAR SUPERIOR because of its versatility, durability, ease to evenly light, thickness, color fastness, diffuseness, and strength.

What makes a larger chroma key backdrop better?

When the backdrop is smaller, the actor has to stand closer to the screen. If your subject is to close to the screen, you may have problems due to the chroma key color reflecting off the screen and bouncing onto your subject. This is called "color bleed" in the industry. Too much bleed can cause the subject to become transparent where the green hits their skin and clothes.  Bleed can be removed by bouncing white light into the problematic areas or by moving your actor further away from the screen. This is one reason why a large backdrop is extremely beneficial for a successful color key. The larger the backdrop, the further you can pull your actor away from it.

Having a larger backdrop also makes it easier to light the backdrop separate from the subject. With more space between the backdrop and the model, you can easily light the backdrop without casting dark shadows on the back of the screen. We recommend placing the subject at least 8'-10' away.

A larger screen will also give you more range of camera movement. If you plan on shooting multiple angles (IE: close-up, wide, side, low POV, moving shots, etc.) then make sure your screen is large enough for its application.

What color is better (BLUE or GREEN)?

Both blue and green work very well for color keying. Green tends to be more popular for DV because the camera's CCD is more sensitive to the frequencies in the green color spectrum and requires slightly less light. Blue, however, can be easier to work with when color bounces onto the subject (bleed). Most of our customers purchase green, but both colors are industry standard. Keep in mind that the Chroma key backdrop shouldn’t resemble colors in your scene. For example, if you are taking photos of a person wearing green clothes, then Chroma key Green may not be your best choice. The same is true for blue. If your subject is wearing blue clothes, then you shouldn’t use a Chroma key Blue backdrop. Photography studios often buy one of each color so they have a Chroma key screen for any situation.