CHROMATTE? Anybody use this?

[DVX100Shooter]

I just watched a DEMO of this product called Chromatte for doing Chroma Key type shoots. Click link below then scroll down to DEMO. I just need to find out if it can be used with the DVX. This product looks pretty impressive.

http://www.virtualsetworks.com/Products.Chromatte.htm

[HorseFilms]

I used a similar setup a few years back using DVCPro cams. It was the easiest chroma setup I've ever done. It took all the work out of lighting because you just worry about lighting your subject and leave the backdrop as it is.

[MrBeaker]

I found the chromatte in a catalog and got very excited. ;D that was until i saw the price. :'( But still a very cool product

[DVX100Shooter]

Yea that price is pretty steep. I went to a local camera store yesterday and priced a set up. $149 for the legs and cross bars case included. The Green Screen fabric was $119 for 10x12 and $199 for 10x24. I may have to go that route for now but I will definitely put the Chromatte on my wishlist to get someday!

[MrBeaker]

It would be nice to have like you said, But the Green fabric is Just fine for now. lol ;D

[DVX100Shooter]

A friend of mine at work was just telling me about another product that cost way cheaper in the $600-800 range that is supposed to be better than using the ring light from Chromatte. He couldnt remember the name of the product though.

[MrBeaker]

well if he remembers difinatly let us know ;D

[andy_starbuck]

I've used the Chromatte and LiteRing in a corporate studio. In that environment the chromatte was pinned to the wall, so it was perfectly flat. And they used a blue LiteRing. The system had a live chromakey processor on it. They weren't capturing in DV and then doing the chromakey in post. I was directing an interview via speakerphone and they were piping the feed to me over an intranet. I looked around the room (on the screen) and saw only the gray background and some small blue back lights near the wall. After a while I said "why don't you turn on the chromakey and let's test it." They said "It's on." I was looking at a virtual set and didn't know it!

I have the background and the Green LiteRing. The resellers usually don't mention it but the small LiteRing is exactly the same diameter as the DVX100 lens. You need to get the large LiteRing. Fortunately, they are the same price.

I am still learning how to use it. You need to get the foreground lighting right. And you have to have enough space between the subjects and the screen to ensure that shadows are not cast from your other lights onto the screen. That's been my main mistake so far. Experimentation continues...

[DVX100Shooter]

So let me ask you this. How much light are those light rings putting out? If I have my talent lit pretty good it would seem like the light ring would be useless. Does the light from the ring show up on talent's face or body or is it like some sort of infrared type light that is sort of invisible and communicates with that grey screen? You do not have to light the screen correct? What size is your screen? How many people can you place in front of your screen using that large ring light you suggested?

[andy_starbuck]

The Lite Ring consists of a circle of either green or blue LEDs. There are the same number of LEDs on the small ring as the large ring. The difference is just the diameter of the hole in the middle and how much tightening you need to do on the three support screws to attach it to the lens. The ring plugs into an intensity controller with a dial on it, and the controller plugs into the wall. You can change the brightness of the light with the controller. Because the LEDs generate coherent light (laser light), the light moves in a straight line to the backdrop, where it reflects right back into the lens. This has two affects. First, there are no shadows, because it is theoretically impossible for the camera to see the shadow from the LEDs. Second, you can move the camera around, including at angles to the chromatte screen, and it will still give a good chromakey without having to re-light everything.

In my tests I had the intensity turned up too bright. And I had my subjects (two people) too close to the backdrop. And they had dark complexions. So I got some edge spill onto my subjects.

What I now know is that the backdrop light needs to be between 1 and 2 stops lower than the proper exposure of the subjects in the key light. I thought I needed bright green chroma color. I didn't realize I just needed enough green to be differentiated. If I were doing the test today, I would set the exposure on the subjects. Ask them to step away. And then use auto iris to set the exposure on the backdrop, adjusting the intensity control until I was between 1 and 2 stops below. Then I’d put them back in the scene and manually return the iris to the original setting.

The subjects have to be 10 feet in front of the screen to minimize the chances of spill. And you need to watch shadows that might be cast on the chromate screen by the key and fill lights, because if they hit the screen it can reflect back to the camera and cause an uneven coloring on the green screen that is hard to key.

I ran one test with two people on screen. Unfortunately, because I was constrained by space I couldn’t get back far enough or get them far enough from the screen to get good results. What I did learn is having them dress in similar colors is really going to simplify the keying. Trying to get a good key on one person wearing a red shirt was okay. But trying to get a good key with the second person wearing turquoise was complicated.

I want to test two people on screen (because I want to try virtual sets). And I want to test one person in action. (I want to match the action with movement in 3D animation and composite it.) But it will probably be some time before I get to do another serious test.

Hope that is useful.

Andy