I have chromakeyed 1920 1080 in Vegas Pro but not with great results. Their is no spill supression in the Vegas keyer. If you add a chroma blur set to medium before the chromakey pluggin it helps with the jaggies, only on DV footage though. Blowing hair, specially blonde hair will have alot of spill and Vegas most likely wont do the job. Keylight and After Effects may be able to help you but for really bad green screen lighting, I use Adobe Ultra. It can key pretty much key anything. I can key footage that would normally be considered unkeyable footage. Hope this helps, Danny Hays

Thanks guys. I have since slept on this.

Just to recap. Yes I've tried Keylight. I haven't tried Ultra even though I have it, heck I haven't even installed it. Sounds slack of me but I try to limit doing things until they need doing maybe this does need doing.

Yes, there's plenty of spill and Keylight should handle that.
BUT. This is a woman dancing with big clumps of hair flying off. The camera is panning to follow her. That fly away hair is motion blurred into the screen color which explains why Keylight and Vegas can't extract a key from it. As well as the motion blur there seems to be some macroblocking in their as well. I can almost get one frame to key OK, move a couple of frames along the T/L in AE or Vegas and it's start again almost.

Bob.

Had enough coffee to get back to this.
Thanks for the private offers of help, I do really appreciate that.

I now realise why this will never fly and I'm kicking myself for not realising this sooner and wasting good peoples time as well as my own.

There's lots of shiny things in the shots. Skin, hair, glasses, guitars and they're all reflecting the blue sky! It might just have worked if the screen was green.

Bob.

To avoid the risk of making more of a fool of myself I tried my skills at CK'ing something kind of shot properly and watched another tutorial on Keylight. Things I learned in no particular order.

1) Keylight is not that great for keying DV, it was designed for keying film or high end digital. There are better tools for chroma subsampled video e.g. Ultra. I haven't got around to trying Ultra myself just yet but I will.
I could improve Keylights performance by blurring the blue channel first. Adjustment of the some of the advanced controls would probably cure some of the edginess but with lots of fly away hair there's nothing to play with.

2) With well shot footage Vegas's CK FX is none too shabby. It lacks the tools to finely finesse edges and suppress spill but heck, for the money you can't complain. With a bit if hard work you could workout how to fudge it.

3) Interlaced 4:2:0 or 4:1:1 video is tricky to key. The chroma samples are split over fields. AE seems to really expose this problem nicely. If the subject is moving quickly and has fine detail I could really see some issues.

4) Using proper material made for use as a key looks like it does help, not just smart marketing. I think if you've got the time to properly light a screen this is not so critical but the tutorial I watched there was no time and only one light. The Reflectomedia seemed to perform very well just thrown over 'something'.

5) Despite all of the above you can get away with a lot by making the subject look like they belong in the background. Just for something to key onto I used a HD DJ motion background. Needless to say the whole composite looks fake and the eye goes looking for more proof e.g. the dodgy edges. So I added a spotlight in AE that lit the foreground and tracked an element in the background. Suddenly it all started to look real even though it was unbelievable. Don't need AE to do this either, you can pull off the same lighting trick in Vegas, a bit more work but again, you can't complain for the price.

Bob.

> 5) Despite all of the above you can get away with a lot by making the subject look like they belong in the background.

Not looking to throw another tool in the works but the Boris RED/BCC keyer tools have a Light Wrap tool which actually uses the background video and wraps it around the edges of the foreground objects and it really helps "sell" the illusion that the person is really in the scene. These are the things that trick our eyes into believing.

BTW, you always want to use green to key digital video because luminance is carried on the green channel and luminance has most of your detail information.

~jr

I did some more tests, this time using my EX1 but still on a blue screen. This was an extreme closeup of my wife flicking her very fine hair around.
Chalk and cheese, the cheap palmcorders sure can produce stunningly good images but when you start futzing with the image digitally the differences between a camera like the HC1 and the EX1 are immediately obvious. Shooting 25p instead of 50i makes a difference too.
After a fairly limited set of testing I've found the very simple keyer in Vegas produces the best outcome with this kind of shot. It's still way short of the results I need but that isn't the fault of the keyer.
Both Ultra and keylight have a lot of smarts but all the single pixel sized hair confounds them. The despotting filters in Keylight see the hair as...spots on the screen. The vector based keying system in Ultra seems to have other issues as well. This might also have something to do with me having to use Vegas to render from XDCAM to uncompressed. Bringing the AVI file back into Vegas the results were not as good as keying the native XDCAM in Vegas, wierd.

My conclusion. What the client wants to do would require the best cameras and optics money can buy. Trying to key fine moving detail at the pixel level needs 4:4:4 sampling, probably shooting 4K would help too. If they had the money for that, many, many other issues could be addressed as well, like getting better looking professional talent :) Their money would be better spent by simply slightly rejigging the story. The background scene that is part of the story could be seen through a window or off the side of a practical set. Problem solved as then only hard solid edges need keying, even a simple mask would do. Even accepting 720p as the deliverable format would make life ever so much easier.

Bob.

One more chroma keyer to throw into the mix is a free keyer that I've used on occasion, it's called "CineGobs Keyer" and it works pretty well. One can never have too many tools in the arsenal.

http://www.cinegobs.com

Tried that one too

One tip I just picked up from elsewhere is to key the hair seperately from the rest of the subject. This makes a lot of sense as I need to preserve transparency in the hair as it moves. The same settings that give me that are no good for the body of the subject.
One mistake I've made in my tests to date is to not turn Detail Off in the camera.
Time permitting in a few days I'll shoot some more tests using a proper CK green screen, better lighting and better camera settings. All in all so far rear projection seems the most promising way to get this kind of shot and it seems a quite common technique for material known to be problematic to key.

Bob.

I do not have much keying knowledge from the software side, but in my opinion, the most important aspect is the screen you are keying to. If your screen is giving a wide chromatic range then no matter what you do, your key will look poor. I have a local company, named 'Bristol' that source a really good range of fabrics and paints. They supply a lot of the local productions like Harry Potter and the Bond films, as well as the Star Wars Prequels. If you have good material, you still have to light well for chromatic consistency, Usually that mean that your principles are not light as you would desire. This is actually quite evident in 'The Phantom Menace'. By the time it came to the all digital films, they were using hte computer to relight these shots - still rubbish looking in my opinion.

I saw a really interesting setup at the show last week. I have seen them before, but I've never stopped to see how they work. The keying material looks grey, but a green light is attached around the lense of the camera, and the camera sees green. Although the brightness can vary, it gives a really good tight chromatic response, so you can get a great key. What is more, the material cuts into a suit really easily.

Generally however, I personally think keys should be used for things that are designed to looked keyed. Pretty much anything that is keyed in an attempt to look realistic just looks rubbish.

"Generally however, I personally think keys should be used for things that are designed to looked keyed. Pretty much anything that is keyed in an attempt to look realistic just looks rubbish."

Robert, I'd have to disagree with you. There are plenty of films out there with "keyed" material and you'd never know the difference.

cheno

Amen to Cheno, there are a lot of keyed scenes you couldn't recognize without knowing it.

Relighting tools really help for that, and there are many of them besides BCC/Boris Red. Also Digital film Tools for example.

I saw a really interesting setup at the show last week. I have seen them before, but I've never stopped to see how they work. The keying material looks grey, but a green light is attached around the lense of the camera, and the camera sees green. Although the brightness can vary, it gives a really good tight chromatic response, so you can get a great key. What is more, the material cuts into a suit really easily.

Looks good at the show.

Or not. It looked terrible when I saw it at NAB.

High level pros have told me they really struggled getting good keys with this system.