Monday, March 18, 2013

Research on 15 of Nuke's Transform Nodes

Hello everybody, tonight (and probably on another day) I will be researching and explaining (trying to) what I learn about 15 of Nuke's transform nodes.  I will be following along with Digital Tutor's "NUKE Node Reference Library: Transform".  I am not sure which one are easy and which ones are hard so I will just start on lesson 1 and move on through 15 (there are 40 videos in the course altogether!).  I'm just going to let you know, the text seems to change sizes at about lesson 12, even though all the text is the same font and size(I can't fix it).  Note: If you want to skim the information, I tried to make it simplified by bolding the most important things.


Lesson 1 (Mirror Node)



The Mirror Node was a very simple node.  Its primary use is to flip an image horizontally or vertically.  This can also be achieved by using the transform node by making the width or height the inverse (if your scale is 1 make it -1).  The instructor mentioned that sometimes it is nice to use this simple node for clarity in your nodes' hierarchy and it is faster to mirror an image.


Location of Mirror Node



Example on How Good Node Hierarchy Should Look




Only Two Options to Choose for Mirror Node Horizontal and Vertical (they are key-able)




Lesson 2 (Tile Node)



With the Tile Node, as the name implies, you can attach it to any other node and get a tiling effect.  Tiling is simple, you decide how many rows and columns of tile you want your image node to have and the later decide on what type of filter you want to use (filters give you varying levels of resolution and sometimes blur effects).  The tile node is also pretty cool because you can create some awesome patterns just by playing around with the rows, columns, and mirrors.  If you want to create your own pattern you can always draw out a shape using the Roto Node and connect it between the Tile Node and the image node you are messing with.

Location of Tile Node


Example of Node Connections With Simple Tile Properties on the Right


Pattern Example 1


Pattern Example 2


Adjusting a Rotoscope Mask can Also Change the Look of Your Shape



Lesson 3 (BlackOutside Node)


The BlackOutside Node allows a user to control Nuke’s Bounding Box.  It can also help fix an image with stretching issues (pixel stretching).  There are some nodes, the instructor mentioned, that can be prone to stretching issues.  The Adjust Bounding Box Node put to a negative value can almost always have that stretching effect.   Also the Transform Node and Reformat Node were briefly noted, have the option of turning it off or on with words “black outside” next to it in the nodes properties panel. The BlackOutside Node wraps a one pixel black border around your image and should fix the stretching problem.

Location of BlackOutside Node


Example of Pixel Stretching in an Image


A Possible Option Available for Switching the BlackOutside Node On or Off



Lesson 4 (AdjBBox Node)


The Adjust Bounding Box Node (or AdjBBox Node) is used to make changes to the bounding box in Nuke.  Because the content that is within the borders of the bounding box is the only thing being processed its size is important.  It is also important to note that the bigger your bounding box is the slower your computer will run (more information is being processed).  He also mentioned that there are times when you need an exact bounding box around your image.  You can use the crop tool (also located in the transform menu set) to get a more tightly cropped image.

Location of AdjustBBox Node

  
Bounding Box Pixel Border (Can Adjust With AdjBBox Node)


Pressing the Two Icon Will Allow for a Tighter Cropping of the Bounding Box


The Crop Node Allows for an Exact Cropping of the Bounding Box



Lesson 5 (Position Node)


The Position Node as the name denotes is used to move the position of an image.  The instructor defined the Position Node as an impulse filter (negates pixel blur).  It was mentioned that the regular Transform Node can used in a similar fashion, but you have a chance of getting a blurry image if it is moved in the wrong way (has cubic filtering assigned).  Luckily, you can set the Transform node to impulse filtering too, but in some cases it might be easier to just throw a Position Node into the Node Graph and use it to move your image around without having to worry about blurring.  Make sure when you use the Position node that it is within the parameters of your bounding box.

Location of Position Node


Can Turn Transform Node to Impulse Filtering


Make Sure Image is Within Bounding Box's Parameters



Lesson 6 (Crop Node)


The Crop Node is similar to the BlackOutside Node and the AdjBBox Node in that it is used to render only what is most needed in the frame.  It is very easy to adjust how large you want your cropping box to be and can save you time when rendering.  You can also animate the Crop Node along with an animation.  Using the Curve Tool Node you can set the curve type to autocrop to automatically crop around your image (sometimes it doesn’t work perfectly), but it is pretty close and can save you time.  It also crops all the frames of your animation!  If you copy the keyed in autocrop settings to your crop tool settings it will have the same effect (and then you can delete the Curve Tool).

Location of Crop Node


Crop Node Controls What Content is Rendered


Example of Cropping Box (Box with crosshairs) With Bounding Box (Box with dotted lines)


Location of CurveTool Node


To Copy, Press "Command + Shift" or "Control + Shift" Click and Drag Keyed In Information (blue parameters settings by dragging the squiggly line box to the other squiggly line box) 


How Auto Cropping Follows Your Animation Object



Lesson 7 (Reformat Node)


As the instructor explained, that Reformat Node allows us to have greater control over resizing our imagesThere three different types of formats: to format, to box, and to scale.  Because all images that you work with can be different sizes and types there is no definite correct format for all images (sometimes you need to try different options to see what works best for you).  There are multiple resize types.  There are also filter options, which control the “sharpening or blurring of your object”

Location of Reformat Node


Example on How Part of an Image Could be Cutoff When Connecting Nodes


Add a Reformat Node In Between Connected Picture Nodes and Wallah!  It Reformats it. 


There are Different Types You Can Choose From 


The Resize Type Can Also Change Your Images' Look (So try multiple types to see which one best matches your image).  There Are Also Format and Filter Options to Choose From.



Lesson 8 (TVIScale Node)


The TVIScale Node can be used to increase an images’ size without majorly compromising the images’ picture quality (or resolution)(usually good for doubling the size).  The instructor explained that TVI stands for “Total Variation In Painting.”  In Painting is what happens when there is data missing and from an image so the computer tries to add more pixels to compensate for lost information.  There are three key options to choose from: Iterations, Lambda, and AIterations can account for pixel smoothness (instead of there being a sharp contrast in the pixels’ colors it kind of gradients them together).  It was said in the tutorial that Iterations are fairly small changes and so leaving it at about “5” is usually good enough (and keeps your render time low).  Lambda is also a tool that allows you to control the sharpness vs. blurriness of an imageA also can affect the sharpness of an image, but it’s main purpose is to make sure that the computer doesn’t have a mathematical error and distort or destroy your image (make sure that it is always set to a value above 0 or you will get some funky results).

Location of TVIScale Node


Regular Resolution "Cubic" Filtering
  

Regular TVIScale Node Filtering 


Three Key Options of TVIScale Node



Lesson 9 (STMap Node)


The STMap is a node that plugs in to multiple sources.  It can plug into another node like the Lens Distortion Node and then connect to another effect node of some kindIf the same node (example: Lens Distortion Node) is connected with and also affecting your main image or animation, you can use the STMap Node to create an effect that can be integrated effectively into your main image (I know this sounds confusing).  Think of it another way, the STMap is like a mediator between the main composition you are working on and the effect you want to add into that composition.  It then (with your tweaking and correct connecting of nodes) tries to best match the effect into your scene without looking fake or cheesy.  The instructor mentioned the use of something like an UV Map (from a 3D application) can be used to change the texture of an object or add a pattern to it.  This is important!  It was also said that UV Passes/Maps need to be at least 32bit or the quality/resolution won’t be very good.  Since that explanation may have been a bit confusing, here are some screenshots to show you what I mean.


Location of STMap Node


Image or Model You Want to Affect
    


Simple Effect or Pattern to Add to Image or Model



One Example of Use: UV Map/Pass of Part of Model



Attach Pattern to UV Map/Pass and Connect Appropriate Nodes to Each Other



How it Looks Integrated Into Image or Scene




Another Image That Can Be Put On the Chair



I know some of you may be thinking, "hey, I can easily do this in Photoshop" (image manipulation).  That is very true, however, can you also use photoshop as a high powered rendering program for images and animations?  Nuke holds an interesting assortment of tools to do multiple things.



Lesson 10 (IDistort Node)



The IDistort Node, as the name implies, is used to distort images and animations in various ways.  As with the STMap, this distortion node is mainly influenced by the other connections that you plug into it.  For example, in the lesson the instructor showed how to make a heat distortion effect and was able to animate it over a static image.  Here are some images showing what I mean.


Location of IDistort Node



Regular Image




Image With the IDistortion Node Attach (With Playing Around With Settings)  If You Look Closely You Can Notice That it Offsets the Elements in the Image.




Look at Current Node Graph Hierarchy




The Image's Look After Adding a Noise Node and a Constant Node (Nodes on Default Settings)




Look at Current Node Graph Hierarchy


The Image's Look After Playing Around With the Noise Node's Settings. (This was actually animated, but I wasn't able to get my screen capture program working to show you)



A Look at Some of the Project's Settings 



Once again Nuke surprises me.  It seems like you can get cool effects with some creativity and trying connecting different nodes to one another to get multiple effects.  You might be able to learn just as much playing with the program as learning about it from an instructor (which I also suggest).



 Lesson 11 (Transform Node: Basic Controls)



The Transform Node is one of the most basic controls, but has some of the most useful functions.  If you want to move an image around in your scene you can use the translate settings or click and drag on the crosshair on the image for speed.  You can also do the same with rotation.  Scaling can also be changed from inside the properties settings, but if you press “shift” then click and drag the outside of your crosshair circle around you can scale your objects that way too.  If you want to move the pivot point (crosshair positioned on your image) of your image or object you can simple press, “control” (or “command” depending on if you are using the mac) and then click and drag it to another position.  You can also key in (setting key frames for animation purposes) the translation, rotation, and scaling settings.  The instructor, however, warned against moving the crosshair after you have animated an image or object as it can (will) change your animation.  The Transform Node is definitely a simple, but useful tool.


Location of Transform Node


Simple Image (Motorcycle) With Transform Node Attached



You Can Translate an Image (Move it in Any Direction)




You Can Scale an Image (In This Case I Shrunk My Image)




You Can Also Rotate an Image (Yes, I Would Park My Motorcycle This Way)




You Can Also Change the Pivot Point or Crosshair to Another Location (I Put it in the Wheel)




A Look at the Transform Node's Properties




Lesson 12 (Motionblur)



The motionblur (in the Transform Node) setting allows you to control the number of samples (amount of fuzziness of your motion).  Motion blur is also determined by the amount of rotation and shutter speed.  The higher you crank up the motion blur the more the sharp edges of your object will get blurred (but it can also slow your machine down if you make it too high).  You could use motion blur for static images too to make the object in motion appear more dynamic and realistic.  For the most part though, motionblur (in my opinion) is the most useful for animations with fast moving objects.

Regular Image of a Fan


Location of Motionblur in Transform Node


Fan Blades With Motionblur at Zero


Fan Blades With Motionblur at Four


An Example Frame of Motionblur Used on a Falling Motorcycle



Lesson 13 (TransformMasked Node)

The TransformMasked Node is almost exactly the same as the Transform Node except that it has an extra mask options that you can use.  Using something like the Roto Node you can draw a shape around the part of the object that you want to mask out or exclusively keep.  You can then connect the Roto Node's shape into the mask connection of the TransformMasked Node (screenshot below illustrates this).  So all in all that TransformMasked Node is a simple node used for quickly masking out parts of images.  



Location of TransformMasked Node




Using the Roto Node to Draw a Mask Around a Section of My Image




A Look at the Node Connections




Transform Settings + Extra Mask Settings




Lesson 14 (CameraShake Node)



The CameraShake Node can be useful to create more dynamic animations or video.  There are multiple settings that you can use to create pleasing effects.  Amplitude affects the amount of offset (the amount the image or animation will move around) or shaking that will occur (additional blur).  You can have it affect everything or you can click on the 2 icon in the CameraShake Node’s properties panel to affect the width or height of the camera shake separately.  You can change the rotation parameter to have the camera randomly shake from side to side or up and down (instructor’s example, gives it a “handy cam look”).  Scaling can give the footage or animation a “pulsing look”.  If the increase any of these first 3 parameters gives you some pixel stretching you can always fix it by using the fixed scale parameter to readjust the image for a frame of two.  The frequency parameter, as the name suggests, affects how often any camera shake is generated.  The lower the frequency the less times the camera will shake, the higher the frequency the more times you will see random camera shaking occurring.  Octaves control the noise (or smoothness of the shaking pixels).  The lower the octaves the smoother the shaking noise will look, but the more octaves you have the more detailed and noisy your shaking will look (“jitteriness of camera shake”).  As was said in the lesson, “shutter controls the amount of motionblur the animation has.”  The sample setting can affect the look (“accuracy”) of the motion blur.  Finally, the CameraShake Node can make an animation or section of camera footage look more interesting and can cause your motion to look more realistic and dynamic.

Location of CameraShake Node

 
CameraShake Properties Settings


Example of Pixel Stretching That Can Occur (Far Right of Image)


Pixel Stretching Can Be Fixed By Increasing the Fixed Scale



Lesson 15 (CornerPin2D Node)(Final Lesson! Well, for me anyways. ;])



The CornerPin2D Node as the instructor so eloquently explained was “used to distort an image through the use of four points.”  He was exactly right!  Depending on where you place the four points of the CornerPin2D Node will determine how the image gets distorted.  Because of this, it works best with square shaped objects.  Here are some images demonstrating one use of this node.

Location of CornerPin Node

  
Image we Want to Use the CornerPin Node On 


Match the Four Points of the Image to the Computer Screen


How I was (following the tutorial) Able to Put the Image on the Screen


How the Integration of the Combined Nodes Looks


Well, everyone I learned just a little bit more about the program known as Nuke.  I feel like I have barely scratched the surface on this useful compositing software.  If you ever want to try Nuke, you can do what my class did and got the two week trial, that way if you really like it, then it might be worth it to you to buy it.  All in all it's a fun program to mess around with.  I hope you might have learned something from my documentation.  See you guys!