perspective camera

The perspective camera is a camera type that is similar to cameras in most 3d packages: it does create a perspective image out of a three dimensional scene, but it does not aim to represent the imperfections and distortions that lenses of photo cameras typically create.

field of view

The value for field of view indicates the angle between the camera and the leftmost and rightmost visible points in the scene (or the top- and bottommost points, if the image is vertical). The exporter normally gets this information from the selected camera in the scene, but the value can be overridden.

camera view angles of 70, 40 and 20 degrees

depth of field

The depth of field indicates how sharp (infinite depth of field) or blurred (shallow depth of field) objects that are not in focus appear. For the perspective camera, this is defined by lens radius. The default value (0) results in an image where everything is in focus. Larger values result in a shallower depth of field.

Focus distance is the distance between the point in the scene that will be in focus and the camera plane.

various Lens Radius settings, from left to right: 0 (infinite depth of field), 0.2, 1, 2. Note that for the different examples, different objects have been used to focus on; the Lens Radius value does not influence the focus distance

shutter

The opening and closing time of the shutter can be entered here. This will be useful once a motion blur feature has been implemented.

lens shift

A shift lens is a lens that can move the position of the horizon up or down without introducing perspective distortion in the vertical direction. Amongst others, this can be useful for architectural perspectives where most of the subject is above the horizon.

The unit of measurement for lens shift is the size (either horizontal or vertical, depending which of the two is biggest) of the image. For example, using a horizontal value of 0.5 will result in an image whose left edge is straight in front of the camera.

a normal perspective view from a horizontal camera; the same view with the camera tilted vertically; the same view using lens shift instead of camera tilt

clipping

Camera clipping hides part of the scene, based on the distance to the camera plane. There are two settings, hither and yonder. When hither is set to 0 and yonder to a value bigger than the size of the model, everything will be visible. The geometry that is hidden by the camera clipping is still taken into account for the lighting calculations.

camera clipping: no camera clipping applied; hither set to 30; yonder set to 50

orthographic camera

The orthographic camera creates an orthographic projection of the scene. This can be used to create straight projections (like a top view or a frontal view) and axonometric projections.

a camera that is looking in a horizontal or vertical direction creates a projection, a tilted camera creates an axonometric view

scale

The scale value sets the scale of the view. The scale number indicates how many model units fit in image. For example, at a scale of one, one model unit will fit exactly in the width of the image (or the height, in case the height is bigger than the width) and at a scale of one hundred, one hundred model units will fit in the image.

clipping / depth of field / focus distance / shutter / lens shift

These settings work the same way as the perspective camera settings.

environment camera

The environment camera creates a 360 degree image from the current camera position. If the camera is completely horizontal, this results in a panoramic image. Amongst others, this can be used to create high dynamic range environment images for image based lighting.

clipping / focus distance / shutter

These settings work the same way as the perspective camera settings.