Keying Tricks – Or loop-arounds???

[Justin Productions]

I would not suggest it. Really not.

Justin Productions
Tangerin01@hotmail.com
Adobe After Effects 6.0 Professional

[Alexander Gao]

Justin, why so cold?

Anyway, I would just suggest you try a luma key first, with key out lighter. If it is footage, that may work if you tweak it some. If you only need a single frame like that though, just mask out what you don’t want in photoshop or something. I hope i helped a little bit at least.

Alexander Gao

“When the revolution happens, I’ll be leading it.”

[Flasheng1]

Thank you very much wango I will continue playing around with it then, trying to see what all is possible with it =). It was for the entire footage (of about 10 seconds or less). Something temporary until we reshoot on a greenscreen and he has the script ready.

long time fan of the cow, first time poster =). I searched around previous posts for something similiar, but didn’t get anything alike, thanks again.

Mindless Studios, Inc.
New Media Technology
http://www.Mindless-Studios.net

J.S Couture Modeling
http://www.jscmodeling.com

[Annaël Beauchemin]

[Dave LaRonde] “It’s challenging enough to pull a flawless key from a properly lit green screen shot. Trying to pull a key from white, 49 times out of 50, will be an excercise in futility. I almost think it’s more cruel to hold out false hope that a luma key is going to cut it.”

Luma keys can work pretty well for sky replacements. When the sky is overexposed and the subjects are properly exposed, I find them even easier than a chroma key.

FlashEng1, if you can, post a picture of one frame of your clip so we can tell you if you’re wasting your time or not.

One other method to luma key is to duplicate the layer and create a B/W matte out of it. For this you desaturate the layer using a Hue/Saturation effect, and then add a Levels or Curve effect. You then crush the blacks and the whites. Your subject should now become a BW silhouette: this is your matte. The advantage of this technique is that you can work within a single color channel (either R, G, or B) which may have a better contrast than the merged RGB channel (this is true especialy with skies).

This method is called procedural mattes. There is few a good tutorials on the net if you google “procedural matte”.

like this one: https://forums.creativecow.net/cgi-bin/new_page_wrapper.cgi?forumid=1&page=https://www.creativecow.net/articles/onneweer_barend/keyingtut/index.html

[Flasheng1]

I will definately attempt this at least! I went ahead and uploaded a picture to:

https://www.mindless-studios.net/ekarl.jpg

Thank you again very much.

Mindless Studios, Inc.
New Media Technology
http://www.Mindless-Studios.net

J.S Couture Modeling
http://www.jscmodeling.com

[Annaël Beauchemin]

forget about it… you will never get a good key out of a picture like that. The picture is very desaturated and the luminance value of the wall is the same as the guy’s shirt and hair.

You could roto him, but it would be easier to just reshoot with a properly lit greenscreen.

[Flasheng1]

I thought it would be awesome to perhaps play with the hue/sat and brightness/contrast enough to export the video again, import it as such, and use that video to get a type of silhouette out of it, and use the silhouette as a mask over the original video to have only him show up on a transparent bg???

But I imagine too much, and don’t know AE’s full capabilities… am I crazy?
Worse case I could also export 10 second jpeg sequence and then edit it in photoshop, and import the sequence to form another video with a transparent background…

It’s really about 10 seconds or less that I needed from it. I know it could mean a lot of work, but for some reason I love pushing myself that way =\…

Mindless Studios, Inc.
New Media Technology
http://www.Mindless-Studios.net

J.S Couture Modeling
http://www.jscmodeling.com

[Steve Roberts]

If you apply Remove Grain, mess with the curves, bump up the saturation to 100, then apply Color Keyer about six times (clicking at different places in the background near the talent), then tweak the Color Key feather, you might get an alpha matte that can be used over the original gray footage. You’ll also need the original footage masked over top to cover some holes in the shirt.

But it will probably look pretty bad. The foreground RGB values match the background RGB values in way too many places, and unless you mask, RGB values are all that any app has to go on.

I concur and also recommend roto or reshoot.

[Flasheng1]

Roto… hmmm time to research this roto and see what it does and how to do it. Thanks AGAIN! hehe.

Mindless Studios, Inc.
New Media Technology
http://www.Mindless-Studios.net

J.S Couture Modeling
http://www.jscmodeling.com

[Steve Roberts]

… and of course, the background isn’t “white”. It’s gray. 🙂 FlashEng1, the keying app doesn’t care what colour the background really is, it only cares what colour the pixels in the image are.

Rotoscoping is the drawing of masks by hand. If you’re clever, you can work “smart” and minimize the amount of work involved by:
– drawing separate masks for static objects
– drawing separate masks for objects that move, but don’t change shape, so you then animate their mask shape by dragging them around
– setting mask shape keyframes at “extreme” positions, allowing AE to automatically interpolate the mask shape between those keyframes
– not assuming that you should draw mask keyframes at every frame or at regular time intervals

(caveat: remember that mask vertices move in straight lines. Smart interpolation can help that, but check the manual)

I think Chris Smith and others posted some rotoscoping tips. You might want to try a search.

But if you reshoot, with an evenly-lit, saturated (no grays, or grayish greens!) greenscreen placed far away from the talent, you’ll be in much better shape. For greenscreen tips, try the Cinematography forum.