Camera for greenscreen

[kris]

I am trying to shoot people with greenscreen but with my Sony handycam DV its hard to remove green colour in Aftereffects becouse of bad compresion of DV. What kind of camera do I have to use so I get good quality video.

 

I have just started to use Aftereffects so maybe the problem is in me but anyhow I think the quality of video makes a difference.

[William Alexander]

There is much more to greenscreen than just the right camera. What can't you remove the way you would like? Post or link to an actual image, it's real cheap and easy to trouble shoot the shot first, instead of buying an expensive prosumer cam and finding you got the same problems...

 

BTW a link to a full res uncompressed frame would be best. I'm willing to take a look and offer my 2 cents to help you to find out if there are some techniques you can use to remove the greenscreen instead of buying a new camera...

 

Cheers

WDA

[kris]

Ok here it is screenshot from AE saved in png.

Do you know maybe any tutorial how to work with greenscreen.

Thanks.

[William Alexander]

There's a lot going on there! Check out the individual channels

 

You might want to at least more evenly light the green screen, maybe a bit brighter with a cooler (blue) light. Move the subject forward a bit (shadows on green screen) and light with a warmer light. Basically lowering the green channel levels on the subject and raising them on the screen is a very good thing;)

 

Question- was there greenscreen on the floor or was it a light colored reflective surface?

 

That should help for the photo shoots.

 

Now removing your greeen screen... not super simple one button stuff ;( Do a google search to find tutorials for: keying a green screen, pulling mattes, garbage masks, despilling. Check out www.dvgarage.com and do another search for 'video compositing' websites. There are a lot of them just cna't remember any specific ones right now.

 

WDA

[kris]

I will try to do that.

Green screen is on the floor also.

[William Alexander]

On the floor... Kind of thought so The green is being reflected up unto the lower body when looking at doing a "Chroma Key" to turn the green screen (green color / channel) into a matte to remove it, the Key starts to include the pants ;(. In other words you need to as much as possible eliminate green reflection or influence on the subject.

 

I haven't used After effects in about 2 months, so I don't want to offer a whole lot of advice app specific. I did however gave it a go in Shake (apple compositor) .... this is what video compositors have to contend with, on a daily basis, LOL you need to create a mask from eirther the green channel or luminance channel, you may need to create mutliple garbage masks to include or exclude the skin and clothing to make the figure go to black or white for the alpha mask. The back lighting of the subject creates a glow around the black areas once again that needs to be addressed and the remaining green contribution removed (despilled). Pretty easy for a still but now your masks need to move with the animation, rotoscoping is how this is typically done (animating a vector based 'drawn' mask) to get the masked selection to follow the animatied areas.

 

Anyway you can make it very easy on yourself if the greenscreen, subject and lighting are set up properly. You might be able to avoid 50-75% of the process described above. Experiement and test in AE and even PSD by looking at the channels and how they can be levels adjusted to create a mask.

 

If you are really interested in learning about this in depth.... www.pixelcorps.com

WDA