Chroma Keying
 

Has anyone done any chroma key work with these cameras? If so how hard was it? I have heard that pulling a key is more difficult with HD than SD. Is that so?

Thanks very much for any thoughts or experience with this.

Bev

I've done it via after effects.. the key looks pretty good... on a still you can see blocky artifacts, but when moving, the key is very crisp, doesn't dance around, looks awesome, especially if you're going to downconvert to SD.

here's a framegrab:

http://www.miketiffee.com/hdv/chromakeytest.jpg

Thank You!
 

Thank you so much for your help Mike! Which camera did you use? Was it the FX1 or the Z1? If it's not too much trouble, what kind of lights?

Thanks again!

Bev

I've also done quite a bit, and will post some of it later in the week for you to play with. Using the 4:2:2 DI, it keys rather nicely, but the transport stream doesn't.
I'm shooting a Z1, using Photoflex softboxes against a Photoflex Flexdrop.

Transport Stream
 

Thank you Douglas for your reply! what exactly do you mean by transport stream? I can't tell whether this is good news about chroma key or not.

Thank you very much for taking the time to post!

Bev

HDV cameras output what's called an M2T file, or a transport stream file. It needs to be decoded. Some people edit transport streams directly, which is foolish, and others use what's called a DI, or digital intermediary. that's the better way to go.

Thanks again!
 

So what is your capture to edit process?

Thank you for your time!

Bev

Bev, I capture using the HDLink software from Cineform. It's PC only, so if you're in the Apple world, it's a little different.
In this capture, the m2t stream is converted to an avi stream. It creates a stream that's much easier for an NLE to work with, correct, and key with.

<<<-- Originally posted by Douglas Spotted Eagle : HDV cameras output what's called an M2T file, or a transport stream file. It needs to be decoded. Some people edit transport streams directly, which is foolish, and others use what's called a DI, or digital intermediary. that's the better way to go. -->>>

Douglas,

why is editing from the transport stream file foolish? is that native editing? pinnacle and canopus have embraced native editing. can you explain your view.

thanks,


joel

Hey Douglas Spotted Eagle,

You mentioned 4:2:2 via DI. Are you saying you get 4:2:2 out of the Z1 via some method such as the component outs?

Thanks.

No. When you use the Cineform DI, the 4:2:0 long GOP is converted to a 4:2:2/2 GOP.

Re: Chroma Keying
 

<<<-- Originally posted by Bev Standish : Has anyone done any chroma key work with these cameras? If so how hard was it? I have heard that pulling a key is more difficult with HD than SD. Is that so? -->>>

just a suggestion,

i do not know if this is mentioned somewhere earlier - but try to experiment with polarising filter whent shooting in front of blue/green screen.

filip