Perfecting The Look - Production Blog

 Lens distortion is the deformation of the footage captured due to the curvature of the lens on the camera. Optical  Distortion is a rotationally symmetric image error which increases from the centre of the image towards the image margin, t here are 2 main types of distortions :  Barrel Distortion - image magnification decreases with increase in distance from the optical axis, hence    straight lines will remain straight towards the center but curve out at the edges of the image. This gives lines a circular, barrel-like shape. Seen in concave spherical and wide angle lens. Pincushion distortion- is the exact opposite of barrel distortion, image magnification increases with increase in distance from the optical axis. Hence,  the edges of the photo can appear to bend in, rather than out. Seen in Convex  spherical  and Telephoto lens. The human eye is capable to perceive distortions only if the geometric error exceeds two per cent. But this might alr...

 Today we learnt about Lens Distortion, how we can remove it and why we re-introduce it at later stages of compositing. So, lens distortion is a product of the curvature of lens being used to shoot the footage, which results in mild curving of lines and edges are supposed to be straight in the captured footage. So the first step is to undistort the footage and export the undistorted footage to Maya for using as backplate while we add our CG assets.  Why we re-introduce Lens Distortion in the end? Once we add our rendered CG assets to the final composition we add distortion to the for ground CG elements, the magnitude of this distortion is the same as the magnitude of undistortion we applied to the footage. So in the end all the elements of the scene have the same amount of lens distortion which helps the CG elements blend with the real footage better. Before we digitally rectify lens distortion we need a reference to correct it. So we capture a checkerboard grid image using th...

 The Corridor Crew guys have been the primary reason for me to choose this module. (well maybe secondary, because there's no way I would have taken an UI/UX based module). I have been watching both their Corridor Digital videos and their react videos on the Corridor Crew channel. They create various parodies like R-Rated Spiderman, Home alone, Nerf John Wick, Portals parody etc. My favorite one their Boston Dynamics bot gone rogue video and their deep fakes. Deep fake is a very interesting concept that teeters on the edge of tech being a boom or a bane for mankind. Deep fakes are essentially AI and deep learning based CG tool that uses a large set of reference images of a person's face and superimposes it on top of the real person's face in a footage. The tool goes through the entire library of images and calculates based on the angle the image was taken, lighting, facial expressions etc and chooses the right ones to merge on top of the footage. Thought not perfect it is go...

 Camera tracking and stabilization is crucial for importing any kind of asset on top of our live footage, as this allows the foreground asset to move in sync with the camera and make it look like its a part of the footage itself. To achieve this we use the Tracker Node in Nuke, which allows us to place tracking points on top of our footage that will be tracked throughout in each and every frame. Choosing Tracking Points - This is the most crucial step in the whole process and will make or break your tracking and stabilization. Preferably, we need to choose points on the footage that have high contrast with its surroundings. WHY? - Choosing high contrast points makes it easier for the Tracker node to keep track of that feature in the footage better. So if there is a clear and sharp distinction in color between the chosen point and its surrounds the automatic tracking will be able to recognize the  point better and keep track of it in each frame. If low contrast points or featur...

  We were told to convert video files into image sequences as its easier and faster for Nuke to process a sequence of images. New Nodes of the week: Retime - Lets you slow down, speed up, or even reverse select frames in a clip without necessarily altering its overall length. Allows you to set an input and output range of frames Grade -  Lets you define white and black points by sampling pixels from the Viewer. Setting the brightest parts of the image to pure white and the darkest to pure black in this manner can help you add punch to overexposed images, for example. You can also use this node for matching foreground plates to background plates. Lens Distortion -it estimates lens distortion in an image and allows us to straighten the distortion through grid detection or manual line detection. It is also used to create STMaps which can be used in other projects as well. Roto - allows you to create and edit Bezier and B-Spline shapes. Add background images by connecting the ...

   Colour Correction, Grading and Colour Theory This week’s class was focused on understanding colour properties and how to grade and correct colour in Nuke. One of the key things here is to match the black and white levels of all the elements, the darkest and lightest points of the footage and the corresponding points of the CG and foreground elements should be the same. This can be achieved using the Grade node with which we can set the black and white levels to match. Different levels of correction – Primary Colour correction aims to correct colour at the highest level, it affects the entire final output. Secondary correction is applied to specific elements individually to make them tonally consistent with the rest of the footage. Colour correction is an essential process to make sure all the elements we add match the footage, whereas colour grading is a more artistic choice that aims to bring about a tone to the full final image output, so this layer is added o...

File types and codecs : Having worked with Photoshop and other video editors before these were quite familiar to me.   Container is what holds the grouping of compressed video as defined by the codec. A container is also referred to as a format. The container takes care of packaging, transport, and presentation. Its also known as a format, some of which are – AVI, MOV , MP4 etc codec is a method for encoding and decoding data. Video editors and other applications use codec to read and write files. Eg. Apple ProRes, H.264 RAW footage is pure visual data obtained directly from the camera sensors, it has no external processing applied to it. Very large file sizes. Log footage is compressed video with adjustments made to the lows and mids by moving it to closer to the highs, creating a low contrast flat image, but since it has more visual info in it, its preferred for colour corrections. Introduction to Nuke NUKE is an industry standard VFX and composting software. It has Nod...