AF100-Atomos Samurai: first test...buzzing artifacts major problem...

Thanks very much for explaining Barry. I also happen to have a blue/green reversable collapsible Muslin 8x8 screen. Now that's probably not nearly big enough if I need to get the subject a good distance away.

So for traditional (no Reflecmedia) green screen, how many feet away from the screen and from the camera should the subject be? I plan to do more tests in a few days with my traditional green screen as well. And I plan to measure the distances.

Is there a standard/rough rule regarding minimum distances of subject to screen and to camera???
 
Have you ever used a white card to bounce light onto a subject? Well, think of what that green screen really is: it's a giant green bounce card. You blast light into it and it bounces onto your subject!

That's why you want the subject as far away as you can get it. Minimum of 10 feet. And that's also why Shooter said to not overlight the greenscreen, because the more light you shoot into it, the more will bounce onto your subject.

And that's why you usually want a decent backlight on your subject, because that will overpower the green spill.
 
I shot a green screen test yesterday and was shocked at the amount of noise from the af100. I was shooting 1080i. I am going to try progressive next and a blue background. If i remember right, 4:2:0 color sampling works better with a blue key?
 
Is there a standard/rough rule regarding minimum distances of subject to screen and to camera???

The rule of thumb is to turn off your key light and look at the monitor. You should see a clean black silhouette of your foreground object against a green background. If you see any green light inside the edges of the black silhouette, it's too close to the screen. Keep moving it away from the screen until the edges of the silhouette are clean and black. Then you can turn the key light back on and adjust the foreground lighting to taste.
 
But just to be clear: pulling a key from all that exes blonde hair is going to be a problem no matter how you lit it.
 
But just to be clear: pulling a key from all that exes blonde hair is going to be a problem no matter how you lit it.

but that's the art of keying!
keylight is king for that kind of edge, and will pull stuff you wouldn't believe.
 
OK but does everything all of you have mentioned apply to the Reflecmedia green screen setup? Because I'm hearing the opposite when it comes to Reflecmedia: that you would need the subject as far away from the camera and as close as possible to the screen to avoid the dreaded greyish halo that appears when the subject is far from the screen. Not doubting what anyone said here, just trying to properly calibrate the Reflecmedia green screen setup.

Unfortunately, I don't have enough space to try the traditional green screen method as my room is too small as is my 7'x7' collapsible green screen. That's why I went for the Reflecmedia chromaflex package.
 
I figured it would be easier if I posted some photos of my Reflecmedia setup which will help you to see what I might be doing wrong. Basically I tried to light the scene with three Litepanels, two for backlighting and one as a keylight. I'm not sure the Litepanels 1x1 are the best lights for this situation, but they're the only lights I have. Reflecmedia lightring is set to -3.

http://gallery.me.com/nicholasnatteau#100471


 
Hello everyone,

I just made a screencast showing the noise issue I keep encountering in Keylight. The noise only appears after applying Keylight.
If anyone has a few moments, please take a look at this short screencast. I would love to know what I'm doing wrong in Keylight and I think this could be very useful for anyone else encountering the same noise issue:

http://vimeo.com/37021102
 
Last edited:
Hello everyone,

I just made a screencast showing the noise issue I keep encountering in Keylight. The noise only appears after applying Keylight.
If anyone has a few moments, please take a look at this short screencast. I would love to know what I'm doing wrong in Keylight and I think this could be very useful for anyone else encountering the same noise issue:

https://vimeo.com/37018411


Can I have the clip to try on?
 
Hello everyone,

I just made a screencast showing the noise issue I keep encountering in Keylight. The noise only appears after applying Keylight.
If anyone has a few moments, please take a look at this short screencast. I would love to know what I'm doing wrong in Keylight and I think this could be very useful for anyone else encountering the same noise issue:


https://vimeo.com/37018411


My first thought when you said noise was the despill being too heavy and having to add some green back to the subject.

Seeing your key, it is very harsh, and your whispy hair (soaked in green) is grey in your key with no apparent hair detail there. And the hair is where your problem is.

But I think you are suffering from the idea that a key is a one click process, whereas keys are usually a composite of several mattes together for the various problem areas, allowing much more subtlety.

I used to composite key (inside the keyer), but for the last few years I've been using a seperate matte combined with a seperately despilled FG, giving me far better and more controllable results.
 
Last edited:
From reading the replies to the initial post, is amazes me when i hear some directors saying that they don't need a DP. Wow, is about all I can say to the use of technique in answers. Getting ready to direct my first short film, and am so damned blessed that EVS in LA turned me onto this site. Thanks one and all.
 
Back
Top