Chroma Key

nidave · Sun 20 Sep, 2009 12.53

I am doing my first ever "Proper" bit of video production for work- its for a Computer based training CD we are producing and I am shooting and editing the introduction.
I am playing about with software and want to test the chroma key on some backgrounds etc. Does anyone know where I can get a sample piece of video of something like a newsreader so I can play ?

Gavin Scott · Sun 20 Sep, 2009 13.21

nidave wrote:I am doing my first ever "Proper" bit of video production for work- its for a Computer based training CD we are producing and I am shooting and editing the introduction.
I am playing about with software and want to test the chroma key on some backgrounds etc. Does anyone know where I can get a sample piece of video of something like a newsreader so I can play ?

http://www.siliconimaging.com/DigitalCi ... otage.html

Scroll down and you can find some HQ clips to play with.

nidave · Sun 20 Sep, 2009 13.31

Gavin Scott wrote:
nidave wrote:I am doing my first ever "Proper" bit of video production for work- its for a Computer based training CD we are producing and I am shooting and editing the introduction.
I am playing about with software and want to test the chroma key on some backgrounds etc. Does anyone know where I can get a sample piece of video of something like a newsreader so I can play ?
http://www.siliconimaging.com/DigitalCi ... otage.html

Scroll down and you can find some HQ clips to play with.

I have tried that and cant seem to be able to play the avi on my pc. any other suggestions?

Gavin Scott · Sun 20 Sep, 2009 13.51

Here's some wee samples from a software package, but useful for trying garbage mattes and working on fine hair etc.

http://up.metropol247.co.uk/Gavin_Scott ... r_Flip.avi

http://up.metropol247.co.uk/Gavin_Scott ... erview.avi

http://up.metropol247.co.uk/Gavin_Scott/Suzy_Medium.avi

http://up.metropol247.co.uk/Gavin_Scott ... anding.avi

http://up.metropol247.co.uk/Gavin_Scott ... ft%202.avi

nidave · Sun 20 Sep, 2009 14.23

that is fantastic exactly what I wanted - thanks.
<Gives Gavin a big Kiss>
Edit: I don't know what a garbage matt is

Gavin Scott · Sun 20 Sep, 2009 14.35

nidave wrote:that is fantastic exactly what I wanted - thanks.
<Gives Gavin a big Kiss>
Edit: I don't know what a garbage matt is

A garbage matte is there to tell the computer which areas of your green screen footage to ignore or remove.

In the clip where Suzy walks into the shot, you can see that there's no green screen in part of the shot - showing the studio and lighting stands etc.

You can create a shape (your garbage matte) to mask off those areas, leaving just the green screen and/or Suzy in the frame. As long as Suzy stays within that area, you don't have to have a full green screen in the whole shot.

Hope that helps.

<kisses Dave back>

nidave · Sun 20 Sep, 2009 14.53

ahhhhh - that would be very useful - I am going to use a tight top 1/3 shot for it and my green fabric is not that big so (if I can work out how to do it) that would make my life easier.

marksi · Sun 20 Sep, 2009 15.00

nidave wrote:ahhhhh - that would be very useful - I am going to use a tight top 1/3 shot for it and my green fabric is not that big so (if I can work out how to do it) that would make my life easier.

Your life will be made substantially easier by not using someone with frizzy hair.

Beep · Sun 20 Sep, 2009 15.14

Whoever did that Green screen had perfect lighting:

The only problem is I didn't tweak the settings so her clothes are see through in places.

Gavin Scott · Sun 20 Sep, 2009 15.15

nidave wrote:ahhhhh - that would be very useful - I am going to use a tight top 1/3 shot for it and my green fabric is not that big so (if I can work out how to do it) that would make my life easier.

Have a look at Adobe Ultra CS3. Its part of the Production Premium Suite, and you can only get it as part of that package.

http://www.adobe.com/ap/products/creati ... /features/

Its very useful for making the best of limited shooting space or a small green screen - and the virtual sets are really cool. They simulate moving camera shots, and foreground objects.

The samples above are from that programme, and you'll be able to see them in action.

It uses a process called Vector Keying. Once your shot is lined up and lit, get your performer to walk out of shot - and film the empty green screen for a few seconds. The software uses that empty shot to set the key - and when your talent walks back in, the computer is able to detect the difference and create a key from that.

There's more to it, but in essence, the results are great even when you have poor shadows and light, and the relatively poor colour of DV video.

It even works with frizzy hair - whether the light is perfect or not.

If you think you like the look of it, I may be able to point you to it.

Beep · Sun 20 Sep, 2009 15.41

http://img62.imageshack.us/img62/5200/comp10000000.png