Best Material for Greenscreen?

V

vcfilms

Well-known member
Hey all,

So I'm currently setting up a small greenscreen studio in my office warehouse. We're looking for the best greenscreen background we can get without painting the walls/creating a cyc (we may do that later if things go well.

I'd like to get some opinions from people with a good amount of experience in this area. What are the best greenscreen backgrounds you can buy for good quality keys. Obviously, camera and lighting setup plays an important part, we already have this stuff covered.

A little about the space, we're looking at a screen about 20feet wide, and 15-17 feet tall, so probably 20x20. Might be able to be smaller, but probably somewhere around there. The back wall is about 10 feet or 15 from camera depending on which wall we put the screen on. Not perfect I know, but that's what we're working with :)

The background I'm looking at so far are:

Filmtools Foam Backed Green screen fabric

http://www.filmtools.com/ligdep/chr...inch-wide-chroma-key-green-screen-fabric.html

Composite Components Green Screen Material

http://www.digitalgreenscreen.com/products/fabric-backings-and-accessories


Any experience with those? Are there others we should be looking at?

We will be stretching them nice and tight in a frame. Similar to how they are displayed on the Composite Components site.

Any feedback would be much appreciated. Thanks :)
 
Last edited:
I've done hours and hours and HOURS of difficult keys.

My favorite solution: take a good greenscreen to a paint store. Have them analyze it and mix you a gallon of flat paint. Home Depot makes paint that works just as well as the $100-a-gallon chroma green.

Paint a totally smooth wall (or even better, the back/bottom side of linoleum with a cyc-curve at the bottom).

I spend more time steaming, and then re-stretching, fabric screens than I care to think about! But a green cyc is heaven.

The foam screens looks promising for location work but they're pretty expensive. The one I've worked with in the past wasn't nearly saturated enough, it was more like chroma seamless paper, kind of a duller green (doesn't mean they all are of course). Duller screens can work OK with raw footage, but tough with compressed files. If you want a permanent screen, screw the fabric. It will always stretch and sag. Paint a smooth and solid surface. Plus, you can re-paint various colors as needed.

2.jpg
 
Thanks for the responses. Interesting David, looks similar to what filmtools is selling. I'll have to look closer into, if cost is similar would probably rather go through Film Tools.

Michael, I would really avoid painting anything with stuff you get at the store. It has far too much Yellow in it and will never have enough saturation. You can probably use it but probably not too easy to key out. I would much prefer painting and doing a cyc, but I'd have to fix some things there before doing that so it may not be possible. For now it's looking like a fabric based solution, I like the fact the foam backed ones absorb light and are less reflective as we're not in a super large space so spill may be a bit of an issue. Def hoping to with a proper cyc down the line.
 
Go get a cheap roll of discount linoleum, 12' wide by 24-30' long and paint the BACK side of the material (first do white primer) with CC digital green or blue. Hang the roll up high and pull down what you need when you need it... a seamless cyc can be achieved with the linoleum by pulling it onto the floor, with a very smooth, very large curve radius that will help you achieve a no horizon void very easily. Just make sure talent doesn't walk too far back onto the material or they will punch through or damage it when it curves up and away from ground level.

Don't think CC paint is worth it? Try taking it to the local hardware store and ask them to match it. They will fail. :)

http://www.digitalgreenscreen.com/products/matching-paints

Regards,

Jim Arthurs
 
In my experience, using the paint match method is great for your base coats. Then use real green screen paint for the top coats.

I have moved from a large studio to a much smaller space. So the foam backed green screen is a much better solution for my needs, allowing me to quickly change my background from green to blue to white to black. Something I could not achieve in a timely manner with a fixed painted cyc.
 
vcfilms said:
Michael, I would really avoid painting anything with stuff you get at the store. It has far too much Yellow in it and will never have enough saturation. You can probably use it but probably not too easy to key out. I would much prefer painting and doing a cyc, but I'd have to fix some things there before doing that so it may not be possible. For now it's looking like a fabric based solution, I like the fact the foam backed ones absorb light and are less reflective as we're not in a super large space so spill may be a bit of an issue. Def hoping to with a proper cyc down the line.
Click to expand...

When I had paint matched to my greenscreen fabrics (using the digital spectrometer-computer-thing at modern paint stores), it didn't have "too much yellow". It was an exact match visually, and showed the same RGB values in testing with daylight flos. It was perfectly saturated.

I've painted an entire ceiling with it and it was the same as keying fabric. And much easier to get a flat, unwrinkled ceiling than fabric.

"Real" Chroma paint comes from a store as well. Do you think they have some magic ingredient? they're using the same pigments as any paint mixer or manufacturer.

It's really bizarre to post something based on testing and the experience of multiple days on set and hours of keying sessions and have someone say "that will never work". And where does "too much yellow" and "not saturated enough" come in? Wild guesses? There are plenty of answers to posts around here that start with "I don't know, but I'd guess...bla bla bla" I test things. I've tested & analyzed every flo, HID, and LED fixture I own for proper gels. I'm not "guessing" if I post that something works.

(That said, I'd love to know how the foam stuff is working for people...)
 
If you go to the stores who mix using the old fashioned carousel of pigments - where it's 3 squirts of this 2 of this and .1 of this, then getting green by them testing your sample often seems to have little bits of white and yellow, as well as the main pigment. I wanted a blue wall, so figured that what I'd do was get them to mix it without the yellow and without the tiny bit of grey and white. They weren't very happy, but I said I wouldn't cause them trouble if it was no good.

I got a big tin of the really great looking blue - that looked to my eye like the Rosco paint I was trying to avoid.

I painted the wall, felt very pleased and went home. Next morning I had a HUGE shock. The paint had slid down the wall overnight, and was a light sky blue at the top and a huge puddle on the floor. I called the manufacturer, and they laughed. It seems the yellow and grey stuff wasn't pigment - it was a binder - the thing that makes the paint breath, so it binds and goes off quickly. They told me that without it, the paint will eventually go off. So I cleared the mess, and after about a week, it was properly dry to the touch. It then had a second coat - but quite thin. Three more days, then another, and then another. What a waste of time and energy. Next time, I just did Rosco, and the green went straight over the blue with no issues at all.
 
KurtF said:
These folks also have foam backed green:

http://www.eefx.com/eefx2/store/chroma_key_greenscreen_bk.html

Prices seem reasonable, scroll down for the sizes and cost.
Click to expand...

I've used these guys several times ranging from 8'X10' to 20' pieces. Works well. I like it better than the thin muslin fabric. One of the orders didn't match the other ones in color but it still keyed fine. Maybe someday I'll actually have a location that I can paint green, blue and white and just leave it alone
 
I have found you get a lot more leeway shooting raw - you can really tweak the greens for a good key color. You can even tweak a shot just to pull the key, and then run the same clip again for skin/etc and use the mask from the first one. Raw even lets me use that dull-ass savage paper, and it's great to have a paper floor and just roll more out when it gets dirty. No matter how many times you scrub and tape the shoes, it eventually goes to hell. Compressed formats, you need to be more in the ballpark.

Interesting about paint binders. I've never had blue paint made, but no problems with the green. I'd guess you'd want a supplier that used the modern color analyzers though. I've had them match really faded trim paint, and some of the pigments come out by drops. Pretty remarkable system.
 
Michael Carter said:
"Real" Chroma paint comes from a store as well. Do you think they have some magic ingredient? they're using the same pigments as any paint mixer or manufacturer.
Click to expand...

In the case of CC's paint, yes, they do have "magic ingredients". By that I mean they use levels of pigments in a specific formulation that the hardware stores simply can't match.

Look, I took a properly prepped sample of CC Digital Green to Lowes and gave it to the paint department with dreams of gallons of cheap knock-off paint... came back later to discover the mixer wide-eyed and a little freaked out. She told me not only that she couldn't match it, but they weren't allowed to even come close to the levels of pigments necessary. Then I took it to a "real" paint store and discovered the same thing.

I have no doubt you can hardware store match any common green screen fabric or even the Rosco paint, as where is the quality control and background experience behind it? As you say, it's "just paint" or garden variety dye techniques. But spend some time and check into the background of CC... you'll see that the mastermind was one of the blue screen matte Gods of the original Apogee, John Dykstra's post Star Wars VFX shop.

I'm sure you're getting excellent results, and that's ultimately all that's important... I started out doing film blue screen on an optical printer and thank my lucky stars everyday that we have these fantastic digital tools with seemingly infinite lee-way in the hands of the masses. I still own a nice Stewart transmission blue screen (a "painted wall" couldn't hack it back then with film on film tech) as an artifact of how bloody hard this process once was.

I just wanted to clear the record with the issue of truly pro paint vs a hardware store or Cowboy Studio style mash-up or equivalent.

Regards,
 
Jim Arthurs said:
Look, I took a properly prepped sample of CC Digital Green to Lowes and gave it to the paint department with dreams of gallons of cheap knock-off paint... came back later to discover the mixer wide-eyed and a little freaked out. She told me not only that she couldn't match it, but they weren't allowed to even come close to the levels of pigments necessary. Then I took it to a "real" paint store and discovered the same thing.
Click to expand...

Interesting. I took my 20' screen in (that's worked on dozens of music vids and TV spots) and the paint was ready in 10 minutes.

I did go through a lot of testing around AE 5 or so, since finding that keylight seems to want its greens darker than other keyers. I was looking for a magic & repeatable combination of RGB values and assuming you wanted everything in the green channel and R&B empty as possible of pixel data. I can't recall the specifics I came up with, but the overall experience sowed me there's some voodoo going on... Keylight seems more concerned with a totally flat screen color, does like it fairly dark, and seems to weigh in the whole green area in its calculations. Option-Eyedropper the green picker with a footage window open and render-off, while Keylight is set to "status" or "Screen matte" and you'll find a lot of variance from shot-to-shot. (It's a great way to pick your green if there's any variance in the screen).

You can also learn a lot by placing an instance of hue-sat before keylight and playing with the green range, brightness, and saturation while watching "status" or "screen matte". That's probably the fastest way to get a visual sense of where your screen should be if you won't be metering it. IRE's a great way to judge screen levels with a WFM, but if you're shooting DSLR or BMC, you need to have those tools separately.

That said, beyond visually realizing "this paint looks exactly the same", everything I learned data-wise with fabric applied to the paint. Maybe I got lucky. I'm also lighting screens with kinos and daylight settings - I found tungsten to be tougher to dial in.
 
You must log in or register to reply here.
Back
Top