Using RGBA in other then what made for

Many people think that RGBA only used with image pixel information and to define the color of an image. But  idea of RGBA can be used to hold masks, depth values, xyz and some other things. when render out form 3D software, in case that it needed some masks for the objects in the scene so it will be easy later to edit in compositing software, use RGBA to hold these masks by assigning these colors to the objects then render it out as a normal image. (red, green, blue, black, white) (be sure not to assign same color to object next to each other). also RGBA can hold XYZ values, which can be very helpful in compositing software. can be use in color correction, relighting, position 2D object in relation the 3D object...so on. 

Things to be considered when integrating CG with Live Action

These are some of the things :

• Light: Direction - intensity - over all color - source count  
• Shadows: Direction - Color - Strength - Soft\sharp - contact shadow 
• Reflection: Strength - over all color - the distortion
• Matching: White & Black Point
                   Depth of Feild
                   Grain
                   Camera Destortion
                   Color Feel 

The 80/20 Rule

The 80/20 Rule is :
Finish 80% of the work (shot \ animation \ Vfx \ anything ) in 20% of Time. But
In 80% left of time Finish the 20% left of the work (this 20% is what give the work the Wow, The Likeness, the acceptance)

Camera shake

One of the ways to make a CG shot look reel is to add randomness and irregularities.
For Example: Camera shake. not always the camera should be smooth, sometime a bit of mistake or shake add the extra touch. 

Realistic monitor replacing

"A nice way to give realistic to monitor replacing is to rebuild all the pixels and flicker as the reel monitor will have while shooting it.then comp it over whatever image you want to replace the screen with." A note from an Interview in (The Art of VFX)... you can read the full article over HERE

THE GIRL WITH THE DRAGON TATTOO (The Art of VFX Interview)

NUKE Render Every other

To render in NUKE Every other (#) frame for fast preview or to check certain things when full length frame play back not necessary, all you need to do is to add x(#) (change # with whatever Number you want) after writing frame start-end. it will be like that ( 1-50x3 ). (see the below image for more clearness). But remember when read it back in nuke change the (missing Frame) sitting in the read property to nearest frame.

2D Motion Vector Pass

If Happen that you Found that your render passes not align with each other in case you have the 2D Motion Vector Pass  rendered in same layer as some passes. that because 2D Motion Vector Pass will make time offset to calculated its data so any other pass render in same as 2D MV pass will have the offset.(If you render 2D Motion Vector Pass in separate layer, you may not have much problem)
So one solution when it is necessary to have it with other passes, is to have it in each render layer (Sound A lot). let's assume that you wont to render AO pass in different layer than the other passes. ( let's say you have now 2 render layer), have 2D Motion Vector Pass in both layers.

Layer / Node Base Compositing

There are so many post around the web talking about this matter, the differences ,the good and the bad.
sure each one has its advantage and disadvantages but some people still prefer one on another.

I have different view about this, it depend on how I like to look at things. well I can sum my view in this Illustration:

The Illustration shows how things organized in each platform (in my view) 

In node base compositing, compositers can see everything lay dawn in front of them which make it easy to keep track on the proces and also faster to find elements around.  

on the other hand, layer base compositing .... it is not that its hard to look for things around but slower in some cases.Compositers  may find it hard to track the process ( not who was working on the project but if the project handed to other compositer). 

But still it all depend on how the compositer organized his project in both cases. 

I hope compositer try both and find the best suit for his\her and adapt techniques from and into each base 

Greeting

Hello Everyone ,

This Bolg will be a place to post Note That I liked in diefferent area in VFX World
and I hope it will be useful for other too