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3D Modelling & Animation. Cameras. Agenda. Maya Camera Principles and Photographic Concepts Camera Types Camera Attributes Movement of Cameras Image Planes Clipping Planes. Camera Principles. Scene. Image. Resulting image is mirrored and inverted
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3D Modelling & Animation Cameras
Agenda • Maya Camera Principles and Photographic Concepts • Camera Types • Camera Attributes • Movement of Cameras • Image Planes • Clipping Planes
Camera Principles Scene Image Resulting image is mirrored and inverted Small aperture results in very long exposures Light Rays Pinhole Camera
Camera Principles Scene Image Increasing the pinhole size provides more light to shorten exposure times but introduces distortion of light rays resulting in poor image quality Light Rays Pinhole Camera
Cameras Principles Scene Image Simple lens refracts light to reduce distortions Light Rays Simple Lens
Cameras Principles Scene Image Compound lens designed to control variety of lens aberrations which effect both image sharpness and colour Light Rays Compound Lens
Physical Lens Features • Base format - The size of the negative / film gate e.g. 35mm - Medium Format - Large Format • Focal Length • Aperture • Depth of Field • Lens aberrations (flare)
Angle of View for 35mm 50mm provides natural perspective for the 35mm format Shorter focal length lenses have angle of view which gives steeper perspective Longer focal length lenses have narrow angle of view which gives flatter perspective
Maya Cameras • Based on 35mm photography • Always in focus • No given depth of field • No aberrations e.g lens flare • Need to create above effects when required
Maya Types • Camera - standalone camera • Camera and Aim - camera with aim to direct at point of interest • Camera Aim and Up - additional control to orientate camera around lens axis
Camera Types Representation in the Maya Environment Camera and Aim Camera Camera, Aim and Up
Camera Movement ‘Subject’ is the point of interest for the selected camera • Zoom - change the magnification of the subject by altering the focal length of the lens • Dolly - change the camera’s perpendicular position relative to the subject • Pan - follow the subject as it moves across the cameras field of view • Track follow the subject from the side usually maintaining a speed equal to the subject’s speed • Follow follow the subject through the scene from behind A typical scenario would apply variations and combinations of the above
Using a ‘dummy object’ on a path to control a camera dummy object Dummy object follows path - camera child of dummy object and follows path - more subtle control of camera movement - less rigid connection
The Hypergraph Window - a schematic representation of all objects in the scene
Image Planes • Cameras can have an image plane placed as a backdrop to provide a background to the camera's field of view or as an aid to modelling geometry against an orthographic image.
B.Sc. (Hons) Multimedia Computing Media Technologies
Clipping Planes • Cameras have adjustable far and near clipping planes • Any object beyond the far clipping pane is not visible • Any object in front of the near clipping plane is not visible • Clipping planes are often referred to as ‘yon’ and ‘hither’ where yon is far and hither is near
Maya Cameras • Based on 35mm photography • Lenses for wide angle , normal, telephoto • Use terminology from the movie industry • Zoom (change focal length of lens) • Dolly - (move toward or away from subject • Track - (side follow subject) • No aberrations e.g lens flare • Always in focus • Animation as individual object and via path-based animation • Use a dummy object as an intermediate connection between camera and path - improves animation of camera