DV Info Net

DV Info Net (https://www.dvinfo.net/forum/)
-   Sony HVR-A1 and HDR-HC Series (https://www.dvinfo.net/forum/sony-hvr-a1-hdr-hc-series/)
-   -   Keying (https://www.dvinfo.net/forum/sony-hvr-a1-hdr-hc-series/69142-keying.html)

Peter Ferling June 8th, 2006 09:08 AM

Keying
 
Has anyone successfully used this camera for keying off of either blue or green screen? I've searched and have not found anything convincing.

I've tried green initially in HDV, it's garbarge of course (it's a balancing act with the studio lighting, and it's hard to get a noiseless image with this cam in such a scenario). I'd have to try capturing via the RGB component for full raster (if that's what I'll get). I plan on upgrading to an HD card, but it'll be a few months yet.

I'd like to incorporate some effects work, and am curious if this camera will do the job, or I'd have to rent.

Nick Outram June 12th, 2006 05:21 AM

Keying
 
Quote:

Originally Posted by Peter Ferling
Has anyone successfully used this camera for keying off of either blue or green screen? I've searched and have not found anything convincing.

I've tried green initially in HDV, it's garbarge of course (it's a balancing act with the studio lighting, and it's hard to get a noiseless image with this cam in such a scenario). I'd have to try capturing via the RGB component for full raster (if that's what I'll get). I plan on upgrading to an HD card, but it'll be a few months yet.

I'd like to incorporate some effects work, and am curious if this camera will do the job, or I'd have to rent.

I'm a bit concerned by this as an upcoming project I want to do involves a green screen section. My situation is made worse in that I do not have proper lighting or a green screen. I am hoping the fact that the film is meant to be a bunch of amatuers messing about making a video will help (!). I have read about 'garbage matts' and also lighting tips on this and other useful forums so am going to give it a go and see if it works.

In theory shouldn't HD give better keying than SD though...?


Regards, Nick.

John Yamamoto June 12th, 2006 07:14 AM

keying ok
 
hi
provided that u make a googd lighting on chroma backgroudn and the subject.

deinterlace it.

apply chroma blur , it means convert it to 4: 4:4

if i m not wrong 4:2:0 sampling is actually swaping in fields it's 4:2:0 and then 4:0:2, so once u merge it's is better. and the chroma blur is a way to soften( yeah! don't panic) the hadr edges.
key as u need. i did try on vegas and very good, someone says use ultra2 u will be more than happy

JY

Rob Gregory-Browne June 12th, 2006 09:02 AM

I did some test footage against green screen with piss poor lighting (just fluorescent overheads) using the A1U. Keyed it with Keylight (possibly the best keyer available - I have Ultra and prefer Keylight) in After Effects and got very clean results.

Had I paid more attention to lighting it would have looked excellent. I'd show you the footage, but it has since been discarded, unfortunately.

When green screening in AE, you might want to look at this great tutorial about super tight junk mattes. It's sometimes a lifesaver:

http://forums.creativecow.net/articl...unk_Mattes.mov

Peter Ferling June 12th, 2006 09:56 AM

The HC1 has to be lit much differently. It has difficulty seeing in dim lit or controlled lighting, (unlike the XL1s, for instance, which has more exposure room at zero gain), I still get a noisy image. Not good for clean keys. Crank up the lights to expose at zero dB, and I blowout my highlights. Tedious.

I've used keylight in AE, even with 4:1:1 stuff and managed acceptable results. I've also done rotoscoping in digital fusion in the past. Fun stuff.

Still, I'm asking a lot from this camera.

Nick Outram June 13th, 2006 06:52 AM

Quote:

Originally Posted by John Yamamoto
hi
provided that u make a googd lighting on chroma backgroudn and the subject.

deinterlace it.

apply chroma blur , it means convert it to 4: 4:4

if i m not wrong 4:2:0 sampling is actually swaping in fields it's 4:2:0 and then 4:0:2, so once u merge it's is better. and the chroma blur is a way to soften( yeah! don't panic) the hadr edges.
key as u need. i did try on vegas and very good, someone says use ultra2 u will be more than happy

JY

Hi John,

not sure I fully understand the numbers you put up there. I will use Vegas (importing the video as an mpeg .m2t HDV file).

I have seen something very similiar to the garbage matts and chroma blur in tutorials somewhere else and will give it a go.

It's a pity that Green screening is not easier to do as it seems an ideal solution to make low/no budget budget shoots look good...

Thanks for replies so far on this.


Nick.

Rob Gregory-Browne June 13th, 2006 07:32 AM

If you want a good green screen key, especially if you don't have optimal footage (and how often IS it?), you might want to invest in After Effects rather than use Vegas.

Vegas can give you decent results, but not great results. There's no real control. With Keylight, you have so many controls that will allow you to compensate for footage problems. Or, if you'd rather, Ultra will help a lot, too.

But Vegas? As much as I love the app (I've been using it since it was called Vegas Video), it just wasn't meant for keying.

P.S. Greenscreening is NOT really that difficult if you have the right tools.

Robert Reinhardt June 20th, 2006 01:51 PM

I recently did a quick test (ok lighting with my Lowel DV Pro 55 Tungsten 5 Light Kit, didn't spend too much time setting up) shooting with the HVR-A1 and I was able to key the green screen pretty well. You can see the footage in a Flash movie here:

http://dev.themakers.com/fp8/video/hdv/hdv_trans.html *


* Flash Player 8 and the newly available On2 VP6 codec support enables you to create alpha channels in Flash Video files.

I agree with previous posts in this thread that Keylight is one of the best (and easiest) filters to chroma key footage in After Effects Professional. (Comes free with After Effects Pro on the install CD.)

I'm not a professional lighting expert, so any advice on how to setup the V-lights in my kit more effectively would be greatly appreciated. At a recent Flash Video workshop I taught in Minneapolis, a creative director from Target was mentioning measuring IRE in the green screen vs. the subject. I'd love to find out more about that too.

-Robert

Robert Young June 20th, 2006 07:39 PM

I have seen very successful green screen footage from Sony HDV.
John Jackman, at DV magazine, did a narrative short film, shot with Sony Z1, called "Windsor's Knot" that utilized some green screen keying. The DVD is commercially available, and his article describing the production/editing details are archived @ DV Mag website. It's also interesting in that he took this project all the way to 35 mm film transfer.
Definitely recommended reading for anyone doing sophisticated HDV projects.
Here's the link: http://www.dv.com/features/features_...leId=174900673


All times are GMT -6. The time now is 11:01 PM.

DV Info Net -- Real Names, Real People, Real Info!
1998-2024 The Digital Video Information Network