Nuke Tutorials and Tools

simple clean screen using IBK colour with un-premult Many of us using stack of IBK colour node with incremental of values to get clean Blue or Green screen. Example below image: Most cases 1 IBK color node will give good result. But in some shots we ended up stacking multiple IBK color node to get the clean screen(plate). When use multiple IBK color node the script became slow, Each node takes more time to produce the result. How do we overcome this slowness ?! Here is the alternate way: I used blur and un-premult nodes to get the similar result. This is much faster then IBK color stacking. Comparison of both method result: Result looks similar. Some shots this method produced better result compare to IBK color stacking. Final result comparison: Here is the steps: 1. Denoise your plate. 2. Create a IBK colour node. Choose your screen type. Play with the values to get the fine result. 3. Add a premult after IBK colour. 4. Create a Blur node. ...

Keying inside Nuke using "expression" node: Green or Blue screen keying is a important task in compositing. Most off the artists (compositors) use any traditional keyer like Primatte, Keylight, UltraKeyer, IBK keyer etc... For complete the keying Task. Most-probably its the traditional way. For more information about keyer tools: http://www.fxguide.com/featured/art_of_keying/ What is happening while we play around (sliders) with above keyer tools. Some color math happening behind while we sampling the screen and adjusting the sliders for fine tuning the Alpha. Why don't we play with those color math function to getting alpha? Here is some example.. How to extracting the alpha channel from green or blue screen footages with some color math using nuke's "Expression" node. 1. Green screen: expression: r*1.5/g*.9 work file: https://skydrive.live.com/redir.aspx?cid=776f8351d9892b6a&resid=776F8351D9892B6A!251&parid=776F8351D9892B6A!133 ...