green screen

[Suerender]

color range from the key-effects tab works pretty well…

[Yussef Cole]

What’s a reasonable price to pay for a green screen? What’s the cheapest you’d pay?

(To add on, in my own way, to this thread…)

[Aharon Rabinowitz]

Keylight keyer is easily the most superior chroma keyer in AE. If you have a decent Green BG (or any color different from your foreground) it can key it out quickly.

A lot of people forget that they really should create a junk matte around their subject. A junk matte is an animated mask that is loosely placed around the subject (it moves with them), but that makes it easier to key because you only have to worry about the greens closest to your subject. Often there is gradation from imperfect illumination (meaning darker and lighter greens), and by matting out the unneeded areas, you have less color variance to compensate for. That will help you a lot.

—————————————-
Aharon Rabinowitz
aharon(AT)yahoo(DOT)com
http://www.allbetsareoff.com
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Creative Cow Master Series DVD
particleIllusion Fusion Volume 1
available @ http://www.pIllusionFusion.com

[Andrew Shanks]

Keylight is the best keyer that comes with After Effects. There are many other options out there, but keylight is all most users will ever need. If you’re finding yourself doing a lot of keying (as a career), you will add other keyers to your toolbag (as some work better than others in certain situations. I generally use primatte as my other keyer of choice (and have zmatte and other misc matte pulling tools as well). Basically keylight is a good all-rounder (if you have a half decent blue or greenscreen). If I can’t get a good key with it, Primatte will usually do the job on nastier keys.

The main tricks with keying are to garbage matte (do a basic matte around the foreground objects you wish to keep), apply the keyer (make sure you know the keyers functions, …this is unfortunately a case where reading the manual is not just a last resort, ….I know I know, i hate reading manuals too, but keylight is very powerful and knowing exactly what all the settings do will make your keying job a lot easier), …if you don’t get a good key first time (and often it is the way, as screens are very rarely perfect), do multiple passes to produce the final matte (Barend Onneweer has a good tutorial on this, see link after this), if you have heavy compression (such as DV) there are techniques to smooth the edges (again a search of this forum will come up with things such as YUV channel bluring and vector blur of edges), and final step is to colour match your foreground element to the background (perhaps adding a bit of light wrap to help blend things). There you go. As mentioned about Barend has written some articles on keying, here are the links:

https://www.creativecow.net/show.php?page=/articles/onneweer_barend/keylight/index.html
https://www.creativecow.net/show.php?page=/articles/onneweer_barend/keyingtut/index.html

https://www.creativecow.net/show.php?page=/articles/onneweer_barend/chromashoot/index.htm

and heres a link to the free video tutorial (by Brian from Total Training) about vector bluring DV keyed edges:

https://www.creativecow.net/articles/total_training/AE65/Vector_Blur/index.html

Hope that helps!

Andrew