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everything Safe said is true and important. especially about lighting screen separately and moving subject further away from that green 'background' so you can light them separately. That means the screen would be wider so you can fill the frame better and you ordered stuff to make it easier to do that.
One thing people sometimes do, for a cleaner key ( chroma key which makes a mask with an alpha channel so you can drop in your new background later ) is to shoot vertical frame. Sounds weird but you get better key that way sometimes, cause your subject fills up the frame more. Look at all the wasted space to the left and right of you horizontal frame. If you key using a vertical frame ( get more of the subject in frame ) you can rotate that in post 90 degrees, scale it down to match your other footage, and it works well for a cleaner key in that situation.
A key makes a mask. Like this... with white and black denoting the mask properties. IN the case below the white stuff will be influenced by color adjustments etc.. while the black stuff is unaffected. That black stuff in essence is your alpha channel. To drop your background into it you may have to invert that, but that's done automatically for you with PPro when you use the chroma key stuff. The main thing is to look at the mask and how CLEAN it is... no speckles of white stuff in black area, very sharply defined lines around the white objects. There are tools in AE to clean up keys like this, and AE is the best place for adobe users to make 'composites' using keys.
you are on the right track and doing well, and it's really cool that you are shooting nice stuff.. so good luck and keep it up !
: )
what's the difference between how green and blue screens are used today making movies and dropping background stuff into the alpha channel during a " live " broadcast" or " Movie" ???
The reason those two chroma key colors exist is important re: how it is handles with live broadcast TV ( like a weather map that gets put behind your favorite morning weatherman ) or making moves with computer generated or other type clips.
The cool thing is that it can be done LIVE. On the set of Pan Am TV show ( which I liked working on as a dolly grip ) it was possible to shoot and composite LIVE because the computer visual special effect guys were on set and could 'drop in' the stuff AS WE SHOT...
It was just to get an idea sometimes ( cause final tweaking of rotoscoping masks would be done fast in post later on ) .. but the basics were there to see LIVE, as you shot ( with video tap on pro cameras ).
Pan Am - Video scenes and visual effects (Exclusive) - YouTube
In essence that's what you want to be clean.. the key … and the masks … and AE is your best bet for this.
But the point I'm making is.... you don't need chroma key to make masks for what you are doing... not really.. you can make the same mask by just sampling a range of colors and making it that way... as long as that range is at least close in hue chroma luma etc...
That's how your new lumetri can do curves based on 'hue v saturation' and so on...
You see that the new thing you ordered with green screen also has white and black. … not blue.
The more you learn the more fun you'll have …. trust me.. it's very cool what we can do at home on small computers and CC stuff.
I agree with what texasbelch has posted; it's a tricky key. You probably need to isolate the hands and use a more aggressive spill suppression and edge correction for that layer, and use a milder key for the rest of the head and torso. Something like this:
It obviously still needs work, but if you use a similar setup, in conjunction with a background colour that works with the key well, it might be ok.
This was done in After Effects using Keylight. I've uploaded the project file here:
I disagree, but I'm using resolve now instead of CS6. Even without going to fusion I could fix that. 24fps is normal so it's not blur, it's the 'key' ( adjustments via simple )
example....
animal with all colors ( no green screen ) selected by a 3d qualifier tool.. ( range of color = each blue lines )…
mask revealed = next image
basic cleaning of key = image 3...
If I can do THAT ( using all the colors shared by nice animal and his surrounding... imagine how clean it would be with your green screen !!!
blur has nothing to do with it...
AE can do this
As interesting as this subject is....
All I can say is, " Thank god the person is frame doesn't have animal ears on his head, and a black nose painted by magic marker with black magic marker lines on cheeks imitating 'whiskers' … and he is not dressed in a skin tight leotard …
That freaked me out and will give me nightmares for the next week probably.
Great contributions and screenshots! I could be wrong, but it seemed you as if at least one of the posts was equating frames per second (fps) with motion blur. Just to clarify my remarks for anyone who may not know the difference, framerate is the number of frames recorded per second (ex: 24fps, 30fps, 60fps). Shutter speed is how long the shutter stays open during recording of the frame and is measured in fractions of a second (ex: 1/50 sec, 1/60, 1/120). Generally, a "cinematic" shutter speed is considered the reciprocal of double your frame rate (see below):
The example below illustrates while using the same framerate (fps), the shutter speed you choose will determine the amount of motion blur present when the subject is moving (in this case, he is running into the frame). Notice that everything that is not moving is sharp, but the person is blurry. In fact, his left foot is less blurry because he's stopping right at that moment.
Going back to Kim's initial post she said, "the person talking is very active with his hands causing and area of green to be associated with the motion."
Because the areas in motion don't have well defined edges (as a result of a slower shutter speed), it is a difficult fix. There are some videos on YouTube that attempt to show how to reduce the effect using After Effects and some 3rd party plugins. This one looked helpful (profanity warning!) How To Key Bad Green Screen Footage - AE Tutorial - YouTube
Hope that helps clarify "the why" and point you towards a suitable post production resolution.
Thank you Texas, for clearing that up.
It might be a good idea to pull a key on a frame that has less motion ( or NO MOTION ) to get the initial key and mask established... then, low and behold, when the stuff that is blurry comes into play it is already separated by the mask and just looks like blurry " hand ", for example... and does not have a bad key around that blur … it's just blurry flesh colored hand.
???
yippee... got that straight !
thanks !
after you drop in your background to the alpha channel ( your mask made from key) you can render it and look at it before exporting..and believe it or not you can actually SEE what is working or not... you can SEE the stuff around this guys hand that is not working....
What to do ???
Golly, go back to key ( mask ) and make adjustments via clean black clean white, grow, shrink, pixel range, all sorts of stuff to adjust to get the clean key... yes, it's true !
Try it and you'll love it.
Hi everyone!
Here's my new green screen set up...
I am using two lights to light the green screen and two to light the subject.
The camera settings as previously mentioned are:
- Changed my Bit Rate / Resolution from: 35 Mbps 1920 x 1080 to 50 Mbps 1920 x 1080
- frame rate from 50i to 25p
- Made sure my premiere settings
- Aim to position my subject three feet from the background
- Light the green background and subject separately
- Changed from auto focus to manual focus
- Gain set to low
- Manually white balance (just looking into how I do this)
- Changed shutter speed to 1/50
- Unable to vertical shoot with our tripod....
Here's the footage (just a quick test!) - much easier to key however I can see a green tint on my colleague's face and I'm still not happy with the resolution - it just doesn't look 'crisp' enough... can anyone offer me any other advice? i'm determined to get the best possible result.
Here's my test footage: Sequence 01 - YouTube
Many thanks
Kim
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