can anyone give me a chromakey noodle that will take out the green screen? I am using RC2. I know that a bunch of differnence keys will do it, but would like to use the chromakey and spill nodes. Bob? thanks. 
Well, there are filters that do this, of course, but let me tell you now that you are going to have a lot of trouble with that screen. 
The trouble is, the actor is casting a shadow on the screen. And, there’s a lot of garbage on the screen itself, caused by folds in the cloth, which is not absolutely uniform to begin with.
What you want as your screen is a perfectly monochrome surface, as created (for example) by a large sheet of professional backdrop material. And you want to put it well back from the actors, brightly but very-evenly lit. You want no shadows on the material from anywhere.
If you are going to do some serious work in this area, consider your local community theatre. Many of these places will rent the hall to you and their stage-crew probably won’t be union. They can rig up a white scrim in the background and light it with whatever tone you want, and make sure that the light won’t fall on the actors.
ur funny. because you are right, and because it was shot in a “professional” studio that my boss signed up for without asking me ($200 per hour). The material is the chroma stuff; looks gray in natural light but the camera has the green LED ring around the lens. yeah. so I get to work with it. which is why I’m asking. I copied Bob’s noodle and it works well; but was looking for something that requires a little less…fiddling with. What’s that old saying “I did not build the engine, the whistle I do not blow,…” I think I could have done better with some green muslim and a $500 light kit in my garage.
Hey! here’s my blend from my succesful key, I hope you enjoy! if you have any questions, just ask! thanks.
P.s. I didn’t use a chroma key, but I found this method to work much better 
I will be making a video tutorial on the method a bit later.
Blend: http://www.ponymoon.com/murphy/introKey.blend.zip
happy blending!
Murphy
Thanks Corey. Let me see if i understand the noodle, Mask.tga is your garbage matte/mask. You separate YCbCr and blur because you, like me, are working with DV tape. The green screen removal is the Channel-colorramp, and edge blending is the -dialate-blur node. Instead of AlphaOver, you mix the original image using the mask as the Factor, ending up with a black-masked image. Color spill takes out any spill, and the HSV - RGB Curve helps you (if needed) correct any color from lighting, etc. yeah?
Yep good job! and then I feed the mask I got from the keying proccess into the final comp alpha so that the rendered result (when rendered in a format that supports it) will contain an alpha channel as well.
I hope it works for you! I’d like to see your result if it does!
100% blender yes, nodes no :eyebrowlift:
Thanks also from my side. I have asked a friend of mine who worked at “Bluebox” ( a german firm specialised in blueBox tecnics) to get good material, but unfortunatly he lost his job one month ago. Problem solved…
If anybody has hints about books, one should read, regarding this issue, I´m always interested.
PLEASE spill the beans!!! HOW did you do it? Did you use the chromakey plugin? what settings??? Help - I need to get all this footage done today/tomorrow.
Yes, I used my chromakey plugin :yes: . The problem is that I have been working on updating it and it’s not finished yet…and it won’t be ready for a bit yet - sorry…you can try with ver1.1 - its not float aware but it should work ok…
here is the setup:
here are the settings that you can’t see…
key color: h=.295 s=.79 v=1
h tol = .07
s tol= .5
v tol= .58
what os are you using? I can try to get more done tonight but I am on linux so if you are on win or mac you will have to compile it yourself when I get it usable
thanks Fligh; I had pappy’s old version that crashed under XP, but your link led me to 1.1 which seems to do things. I’ve PM’ed him, but for noobs like me, it’s all in the Settings. I am spending my nights and weekends documenting the plugins for everyone (see http://mediawiki.blender.org/index.php/Manual/Sequence_Plugins ) and am just a little frustrated at even being given a HINT as to how they work and how to use them - so much doco to write it is overwhelming. So. Pap, throw me a bone here and at least get me started with the settings you used. I can go fromthere, but just seeing the panel and clicking randomly
does not give good results.
Pap: we cross posted. THANK YOU PAP!!! Is the panel going to change, cause if so I will hold off on wiki for your plugin. I am XP and lost my ability to compile about 10 years ago.
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Here is my take on it. I preprocessed the image before trying to pull a key (at least with this image). I then used a channel keyer and used the green channel. I then use a color band to adjust the levels of the white/black of the mask generated. Then I blur the mask a bit and erode it to make it fit a bit better. Then I set the mask as the alpha channel of the original image and do a color spill on the result.
Close up of the pre-processing
Cheers,
Bob
PS. Paprmh, thats an awesome plug-in. I looked at it before, but I guess I didn’t understand everything you were doing.
Hey guys, really sorry to be a bum about this, but I posted the BG photo when I wasn’t supposed to, I got it from sxc.hu, and part of the agreement is that I won’t distribute or share the photo. So I took it down, but it looks like it has been used! so, if you would use a different BG image, that would be great. I’m really sorry!
Thanks!
Murphy
Aim first, then shoot
no problem.
Thanks so much!
CoreyAvitar: also no problem…I had also looked at your thread and played with your stuff a bit too - then was lazy and used your bg pic because it was handy…my apologies
yeah, me neither :o… thats why the code is…um…lets just say its interesting…it’s only redeming value is that it seems to work pretty well sometimes. Your nodes are going to prove much better in the long run, I just thought it would be fun to give you and your node fans a bit of competition so I started updating the old plugin :evilgrin:
Roger: No, don’t post in the wiki… I never thought it was good enough to submit the plugin to either sirdude ( he is the one who has the plugin repository at umn.edu ) or the script dev mailing list so it isn’t an “official” plugin. In fact, after the nodes came out and bob started with the matte nodes, I gave up on it completely. Like I told bob above, I only meant to get people fired up and seeing if they could beat my efforts. And yes I will be changing the layout a bit yet… the zoom buttons are already gone - now you can zoom the preview window so they are no longer needed. The final blur buttons are probably toast too…
BTW: can you guys get noninterlaced video to work with? it’s much harder to key interlaced frames.
@Paprmh: ok on the holdoff. I worked with your seq plugin all day. I found that it crashes blender after rendering 80-100 NTSC frames; kindofa pain. As usualy, seq plugins are SO much faster than nodes. At least, yours started off at like .4 secs per frame, but as it neared frame 60 it was like 8 seconds per. Need some code cleanup I think.
@Bob: Thank you!!! as well as the Channel-ColorRamp combo worked, I would abandon the Chromakey node. I noticed in your preprocess you did for me that you did a 2x2 blur on Cr and Cb, not the 4x1 in your original tut. Have you changed your thinking on that?
For everyone’s benefit, I enhanced Bob’s noodle to add Brightness control and Shadow. Brightness control: I felt he was a little overlit, so I took the Luminance channel (Y) through a ColorRamp, and changed the White to a light gray (.9, .9, .9). The result is that all luminance (brightness) is now scaled down a little. As Bob mentions in his tut, the eye is really sensitive to brightness, so a little adjustment there goes a long way:
To add a shadow, I took the matte created by Bob’s Channel-Colorramp-blur-erode noodle and plugged that in to a color ramp of black to gray, blurred the heck out of it, offset it (Translate) a bunch to simulate how light would travel from the apparent hot spots on the foreground actor, and fed that as the Factor to a color node. The image from a color node came from a picture of a wood panelled wall I took, scaled down from my camera’s resoultion of 1800 to 720. As a result, where the shadow would fall, the colors in the background are darker by 50% (see the color curve box). The resulting image has a shadow. When the actor is placed in front and offset, it looks like he’s casting a shadow on the background.
I find that fake shadows really help convince the eye that it’s real, and not just pasted over a background, if you brain expects a shadow to be there.