green screen results using sample video from VS 10 not good

[mtaddeo]

Hi Everyone,

I use MS Pro 7.3 and have never used the green screen overlay options but have a project I would like to try so I am trying to learn how to do this.

I'm using the sample video from VS 10 (girl holding camcorder and walking forward on green background) and have Overlay Options: Type Chroma Key but a green shadow surrounds the girl. I've adjusted the Similarity and blend/opacity but can't get rid of the green shadow. Is this the best this feature gets without using another filter (I saw a post for that)?

Just need to know if I'm missing something I should be doing before I start downloading filters, etc. Thanks for any help.

Mary T

[Devil]

I don't know the VS clip, but I've tried it with the Video_11.mpg sample in MSP8 (can't remember if it's in earlier editions). It always leaves a thin green line, esp. on the right side of the girl. However, if I do it on a decently shot DV clip, it doesn't. Why?

Well, there may be two reasons. It may be that either there are greenish reflections from the background on the girl's clothing or there are compression artefacts in MPEG-2, kinda sorta anti-aliasing the pink>green interface. Certainly, if you look carefully, you can see the line of colour before you apply the overlay. If you put the eyedropper on this line, you can eliminate it, but you will get some moiré artefacts in its place.

I wouldn't worry too much: I've never had any problem in practical applications.

[Terry Stetler]

Parameters to try;

Eyedropper: her shadow on the background (to her right)
Key: Chromakey
Blend/Opacity: 34%
Similarity: 22%

Because of its irregular shading hair often shows more spillover (that's what the fringe is called) than more regular shades, and is more difficult to clean up.

When shooting my own keys I try to use a light amber colored hair light (spot behind/above the subject) to minimize the effect. Amber neutralizes the green spillover while highlighting the hair and filling the shadows. If using sunlight then a small gold reflector does the trick.

Amber side fill lights are also useful if spillover is a problem on the sides of the subject(s), again neutrailizing the green.

[Jerry Jones]

For truly GREAT chromakey effects, I use Serious Magic's ULTRA and VISUAL COMMUNICATOR PRO products:

http://tinyurl.com/4usfg

Jerry Jones
http://www.jonesgroup.net

[Jerry Jones]

Also, Nick Jushchyshyn has written some tutorials here:

http://tinyurl.com/o2s7a

Jerry Jones
http://www.jonesgroup.net