EX1 & Green Screen
 

What would be an overall great camera setting to use the EX1 for chroma key work? Frame rates, bitrate, etc....

Thanks for any suggestions.

Joel Brooks
Moments in Time

Definitely shoot progressive, not interlaced. I would personally shoot 1080p.

1080/24p at XDCAM EX. Bottom line with shooting green screen is proper lighting. Get that right and even DV can be properly keyed.

Green Screen Lighting

BlueSky - Lighting examples-Green Screen

Well you also of course need a good keyer in post- sometimes this means plugins. I get a lot of love with DV Garage and also G-Nicer.

dvGarage - Training and Tools for the Next Generation

Nattress: Film Effects: G Nicer 4:1:1

Assuming you're on Mac of course.

Also, Ultimatte if you can afford it:

http://www.ultimatte.com/

-Noah

My First Chromakey Attempt on Vimeo

This is wat I shot at home with simple equipment. setting was 720-50p. Held out quite well to my liking. If I had proper lighting I think it would be even better. The green screen caused me USD11 or so. It was edited in Vegas.

Basically as has been said above. Shoot progressive, turn the detail down or off (gives smother edges) and light it well. Use a subtle backlight to add separation between the foreground and background. The background should be uniformly lit with a luminance level somewhere between 60 and 75 ire. for a head and shoulders shot I normally use a pair of Arri 650's on full flood to light the background with some green or blue (for blue screen) gels. Try to keep the background lights to the rear of the subject to minimise spill. The gels help prevent low saturation highlights. Then I light the subject with a soft key light (Arri 300 with soft box or 4 tube fluorescent), a further Arri 300 or Arri 150 as fill and another 150 as backlight. Get as much distance as you can between the subject and background so you can throw the background as far out of focus as possible to smooth out any creases, marks or other flaws.

Here's an example:

http://www.hawaiigoesfishing.com/vid...t_2009_psa.mov

Cine 4 setting used.

Two lights on an EEFX.com green screen. Exposed at 50 IRE.

One light on the subject.

No backlight

Detail turned off.

Primatte used for keying.

Good clean keying Dean 10/10 :)

Thanks, Alister.

Here's another sample.

http://www.hawaiigoesfishing.com/vid...erey_intro.mov

Note Cindy's hair.

Same setup. Two lights to illuminate the green screen. The keylight had a slight diffusion to simulate the slightly diffused sunlight due to the volcanic haze that's dominating the skies in Kailua-Kona lately.

By the way, these are all shot at 1080p30.

I applaud your use of single point lighting. Looks so much more natural than my old school setup. Had a very long discussion with a good DP on the way home from a shoot about the need to use fewer lights to get a more natural look. Many of my clients like to have shots that deliberately look "lit", which makes them un-natural. With camera like the EX capable of producing natural, un-processed images a like the lit look less and less.

I'm trying for as much realism as possible, making it look like it was shot in the field.

One of the typical comments I've had here from other professionals who are in the business said they were wondering how we shot it to make it look so good. They thought it was in the field and we brought a reflector or supplementary lighting, etc.

In some of the early morning "standups", I faced a problem where the light matched the background yet things didn't look right. Wasn't the direction, quality or quantity of light. After pondering it for a few minutes I realized it was a matter of the color of the shadows.

With early morning light from a cloudless sky, the light source can be somewhat warm. But it's warm compared to the color of the shadows which are being filled by that big blue sky. To simulate that, I placed a large blue reflector opposite of the key light and the end result was a lot more realistic.

Dean's approach is a good one, I think. For years the look of a keyed stand-up has been linked with studio lighting and strong backlight and I'm not really sure why that has to be the case. There isn't a technical need for backlight when keying, in fact it will make it harder sometimes to key out hair as you can really see the edges get crispy. Of course you have to watch for green contamination on your subject, but that's why it's important to have a big enough backing to be able to move your subject far enough away to avoid this when possible, and also have a good set of keying tools. Consider all of the CGI shots that we don't notice in movies--the main trick is that the lighting matches the background as completely as possible.

If I need to match a foreground element to be keyed into a daylight scene, I'd rather opt to shoot the foreground outside, adding whatever lighting I would have if we were shooting the whole thing practically. Even the sound will be more accurate as long as you are in the right environment (freeway traffic might spoil the effect of Dean's video!) Otherwise if I had to create a daylight look in the studio, I'd want to have a large overhead bounce for sky blue ambience.

When I made a little short last year that required a couple of greenscreen elements, I had barely enough to make it work (my girlfriend and I made the film together and one of her trips to the garment district to find wardrobe I asked her to bring back a hunk of bright green material, which she did--it was just barely big enough to cover her for the required shots). For the "Fargo" shot, it was much easier and more effective to shoot in my yard--I waited until late afternoon when we were in shadow and the light closely matched the Minnesota "gloom". No additional lighting required, and a near-perfect match (plus judicious color correction). The "When Harry Met Sally" clip required an bright 80's rom-com look with a fat backlight, while "Office Space" was somewhat flat and desaturated to match the source material. The rest of the clips are practical. I should point out that I am just above hack level when it comes to keying but I was happy enough with the results with this film.

What a fun short!

Nicely done...especially the Benny Hill-esque continuity issue with the croissant and the coffee.

That was fun stuff, Charles.

You managed to match the look quite nicely throughout! Best of all, although I watched it for technical reasons, I found myself enjoying the story even more.

All those are good keyers, but for the price, especially when compared to Ultimate, you can't go wrong with Shake. The keyers are great and you get so much more with the package on the top of that.

what lights
 

Hi Dean,

Great natural looking key - could you provide more info on your lighting set-ups in the studio and out in the field???

cheers

Hi Wes....

The lighting is very simple. Just two Lowel Tota lights to illuminate 10-foot-wide EEFX.com green screen. Then a single light to illuminate the talent.

The green screen is exposed at 50 IRE to put it right in the middle of the exposure scale. It maximizes any chroma information and gives the keyer the best chance of getting the most out of the available image data. It also minimizes flare which then helps with keying fine objects. If the green is too bright it starts to bleed into the foreground elements and makes keying more difficult.

Also, you must white balance for the background light. Not the foreground light. That green needs to be exposed and recorded as accurately as possible. While many keyers can compensate for problems, try to alleviate problems at the start so you're not facing issues in post.

Cindy is lit separately. The light is adjusted to get her right where she needs to be on the exposure scale, independently of th background.

The background plate is shot in advance. Then the single Lowel DP light in the studio is adjusted to match the angle and quality of the light in the background plate.

I might make a simple "model" to take into the field that will allow me to quickly record the lighting qualities and make it easier to duplicate the lighting conditions in the studio.

As for outdoor lighting, it's usually early morning or late afternoon.

Hope this helps!

Dean: How are you measuring that 50 IRE? And you're saying you balance for the green regardless of the subject lighting?

Charles: Super short. Congrats.

Mike...

I use camera zebras to get the 50 IRE. Set the zebras at 50 and make adjustments until the green screen is barely covered in them.

As for white balancing for the green screen illumination: absolutely.

Consider this: It's the computer's ability to sort out what is green and what isn't that make a keyer work. The purer the color, the easier it is for the computer program to sort out the difference between the background and foreground.

By white balancing for the light hitting the green screen you help ensure that you're getting the cleanest primary color possible whether it's green, blue or red.

You could illuminate the green screen with a green light but that's not necessary. Besides, if you're doing a full-body shot then you can't have that green light falling all over the talent.

Some people use in-camera settings to achieve a "look" but sometimes those settings can make it really tough to pull a key. If the look involves desaturating the color, that's a huge problem. In fact anything that skews the cameras response to color can create serious problems in post because the keyer depends entirely upon chroma information to pull a key. Give it bad chroma information and you're going to get a bad key. Better to create that "look" in post after the keying step.

Thanks, Dean. But does that still mean you're setting your aperture for subject first? Say I've got a location lighting setup that yields an aperture of 3.4 (and no higher) for best exposure of the subject under tungsten. Do you then remove the subject, fill the screen with the green, and check that your zebra's are blossoming at 50%?

Mike...

I'm shooting in a studio.

So I'll set the green screen lighting first, then place the talent. Then the lighting for the talent is set up and adjusted to suit the exposure established by the green screen, and to match the direction and quality of light in the background plate.

Dean, I've been inspired with your flawless chroma keys you've shown here. I'm also trying to do some keying of people into natural settings.

I'm evaluating Primatte Keyer Pro 4 based on yours and other recommendations within Final Cut Pro 6. I like all the flexibility of the controls, although I'm having some trouble with blond hair on a blue screen, but the main problem I'm having is that it's really slow to render. Like 40 seconds of keyed EX1 footage takes 20 minutes to render. And it's really slow when adjusting Primatte. I'm using a very fast Mac Pro 8 Core with plenty of memory.

Do you have any suggestions? I like it but if it's this slow I probably need to look elsewhere. The Motion Primatte lite is basically instant rendering. Right now it's using only 1 core or sof of processing power, from what I can see.

Are there things I should try to speed it up?

Has anybody tried using Shake 4.1 for chroma keying? Any other recommendations?

Thanks for any advice.

Keith...

I'm using Primatte from within After Effects, and it's making use of the graphics card as well as the eight processors. So that could account for a considerable speed difference. Other than increasing the number of "instances" in Qmaster I don't really know if anything can be done to help FCP access all eight processors and make full use of the GPU. Maybe that's something which might be found in a future release of FCP?

For keying around hair you might want to key the hair separately from the rest of the talent. I often do that, and a lot of other compositors do the same. Key settings that work for a white blouse, for example, might not be ideal for a wedding veil or smoke.

In Primatte there are some refinement tools. The ones that might be of particular value for hair is "spill plus" and "spill minus". And "matte plus" and "matte minus". These will let you "creep" toward a working setting. Each time you drag the cursor through the problem area, it makes a slight adjustment. Make sure you're using a "point" selector instead of a "rectangular" selector.

Another very powerful tool is "lightwrap". Works great to integrate edges of the foreground into the background, and can even help induce realistic "flare" when a foreground item intersects a bright object in the background. But it usually kills off fine detail when it comes to wispy hair.

So there are lots of tools in Primatte. Just keep in mind that you may need to do multiple keys to solve different problems. Rarely does a single key setting work perfectly for all elements in an entire scene.

Also, the better you get, the more critical you become, and the longer it takes!

I'm impressed by the keying too (I'm also impressed by Cindy!). Speaking of Cindy, what did you use to light her? I don't think you said, only that you used "A single light".

Hi Dean

Thanks for the info. I don't know how to do multiple keys such as for the hair, but obviously it's possible so I'll figure that out. I have played around with all kinds of settings, including the light wrap, and I like it.

However, the pokiness is getting me down. Even before rendering it's really slow, so it makes trying things out and looking at the preview in the canvas painful. I have a really fast graphics card, an ATI Radeon HD 3870 GPU and Primatte is an FXPlug so it should be using the GPU of the Radeon.

I've heard some complaints about Primatte's speed with FCP. I also just tried using it in Motion and it still seems as slow. I don't have Adobe After effects.

Do you use Final Cut Pro? If you have a moment could you see if Primatte is slow for you there? I don't know if I can afford the $900 bucks right now for After Effects since I use other apps for what After effects can do.

Thanks for the advice and help.

-Keith

Cindy? Hehe. Lots of guys are impressed, too. She used to be a TV news reporter here, was doing news on the radio, and even played a role or two on ABC's "Lost". She's gradually developing a different personna for this type of work. It's not the usual newsy approach. It's more of a conversational style.

I use a Lowel DP light on her. Sometimes I'll use a diffuser, depending on what the background plate looks like. For example, one scene was in Kona where volcanic haze is often a problem. I softened the sunlight just a little to match the types of shadows I was seeing.

We're always half-joking about what she needs to wear for a particular shoot. Recently I told her she was going to be at a reservoir in breezy and chilly Nuuanu valley, so bring a jacket.

Keith...

Yep, I use FCP for all my editing.

To do multiple keys, you will need to create a different layer for each key. Mask off the area you want to key, then work on that section. It means being able to move the mask if the area you want keyed also moves. Can be very painful in FCP. So if you're doing a lot of keying you might want to consider investing in AE.

FCP is a great editor. But not so good when it comes to doing composites. That's really the realm of AE. BTW, AE is a lousy editor.

I don't know if the version of Primatte I have will work in FCP as it's really intended for After Effects. I'm just guessing but the speed problem might be FCP's inability to work with all the processors on the Intel Mac. I believe Primatte is very processor intensive with all the calculations it has to make on how it differentiates between what's green and what's not. I've noticed that FCP isn't making full use of available resources with ordinary rendering, too. Observing how it works through the Activity Monitor, I don't see all eight columns of the readout maxing out. With AE, all eight columns are maxed out.

I can't believe people that look like her work in RADIO. Thanks for the insights though. Keep the faith Dean, must be tough over there in Hawaii, with Cindy, the deep sea fishing, the beaches etc. I feel for you.

Dean, what version of After Effects are you using? Maybe I can get a good deal on a version earlier than CS4. I could also download a trial I think and see if Primatte works faster with it. Regarding FCP using multiple CPUs I think you are right it should be a little better than it is right now at that.

Keith...

I'm using CS3. Production version.

Yep, life can be tough... :-)

Seriously, I've been though a couple of trips where the sea was so rough you had to be on all fours to get from the fighting chair to the cabin. Lots of bouts of sea sickness. And a few trips where days were spent in the middle of nowhere with no fish.

It beats canning pineapples.

So THAT'S what it means to be "on the dole"? ;)

double post

No, that's what it means to get "canned". . . :-)

It was that summer job as a teenager, operating a palletizer in 90-degree steam heat for 8 hours a day, is what drove me and my friends to get college degrees.

Touche, Dean!! ;)

I was watching a program this morning on the Discovery Channel about canned foods and never realized that there were few people other than those in Hawaii who even knew what pineapple was until canned foods became available.

Have fun over there. Your state is one place I'd love to see before I shuffle off this mortal coil.
dave

p.s. sorry for the threadc**p folks....back to the show

I've had good results with Keylight within FCP: The Foundry Keylight - PlugInFinder | Toolfarm's Plug-in Finder

Here's a little green screen video I did for my church: http://robcollins.net/gnn

Didn't see this thread before!
I'm trying to shoot an extreme closeup of talent with long hair with them deliberately flicking their hair around to then be keyed. Delivery is 1080p. So far I'm not having a lot of success.
So far things I've done wrong and will correct in my next test:

1) Using a blue instead of green screen.
2) Forgetting to turn detail Off.

I'm finding the single strands of hair are a nightmare to key when they're in motion.
Tools I have are Vegas's basic keyer, Keylight in AE and Ultra. Oddly enough to date Vegas's basic keyer seems to do the best job.
I've also taken on board suggestions to key the hair seperately. This might not be a trivial task as the talent will be moving their head a lot but indeed keyer settings that seem to work OK for the hair do not work well for the rest of the frame and edge correction is impossible on such fine hair but OK on the body of the talent.

Any and all suggestions appreciated, I'm kind of at the point of thinking rear projection would be a better option than keying.

I've had the same success using the keyer in Vegas over some others. And with Vegas I can edit my video with all the other elements and not export video to be keyed and then importing back in, etc.

I've wondered what some of the tricks are to cut down on motion when keying; meaning when you get motion blur, the key falls apart. I'm trying to learn what can be done to minimize that other than not having the talent move hands too fast, etc. But my client is part Italian from New Jersey, so he talks using his hands a lot. But for things other than talking heads, such as jumping, dancing, etc.

I'm guessing the more expensive your key program the better your results. Obviously Hollywood can accomplish very clean chroma-key but then I'm sure using 4:2:2 and big budgets helps a lot.

The "key" in keying is the program's ability to distinguish what's green, what's not and what's in-between.

Subtle discrimination and spill control is what makes Primatte so powerful. To eliminate green edges Keylight has to cut away at the foreground element. It works but it's a bit crude. The equivalent of chopping away anything that doesn't look good, even though it might contribute to certain essential foreground elements.

Programs such as Primatte and Ultimatte turn most of those edges into transitions.

So elements such as smoke, fine hair and even translucent veils and plastic can be keyed.

You don't need 4:2:2 to get a good key, although it certainly helps. XDCamEX, with it's 4:2:0 sampling provides very good keying data partly because of the full 1920x1080 raster.

Just to re-iterate: it helps a LOT to get a good shot from the start. Make sure your optics are as clean. Expose the green screen at 50 IRE and white balance based on the light that illuminates your green screen, or at least make sure it's green and not some other blend of colors. For example, it's OK to light your green screen with green lights. Just make sure you're not spilling all over your foreground elements and talent. Turn off your edge sharpening in the camera. Shoot progressive at max resolution of 1080, and not interlaced. Keep your gain at zero.

If you can record the 4:2:2 output of the camera that's even better. If not, the 4:2:0 sampling on the SxS card works well, too.

Sorry for the dumb ?
 

I am just starting out I have an FX7 that shoots 1080i. I don't think I can do 1080p but I'm not sure. My concern is I keep reading on this thread that you should use p. Any info is appreciated fellas. Thanks...

For interlaced material, the usual procedure is to de-interlace first. Do the composite. Then re-interlace.