// set viewer's position in the scene (however, a camera is not required)
camera
{
// (---camera types---)
// perspective (default) | orthographic | fisheye |
// ultra_wide_angle | omnimax | panoramic | cylinder 1 to 4 | spherical

 location  < 0, 1, -5 >           // position of camera <x,y,z>
        
 direction 2.0*z                  // older syntax, where to look <x,y,z> & zoom
        
// sky       y                    // for tilting the camera
        
 up        y                      // which way is +up <x,y,z> (aspect ratio with x)
 right x*image_width/image_height // which way is +right <x,y,z> (aspect ratio with y)
                                  // note that non-perpendicular axes can cause warnings
           
 look_at   < 0, 0, 0 >            // center of view at this point <x,y,z>
        
// angle 67                       // overrides "direction" with specific angle (is not degrees)
        
// normal { ripples 0.2 }         // perturb the camera lens with a pattern
        
// (---focal blur extras---)
// aperture 0.2                   // [0...N] larger is narrower depth of field (blurrier)
// blur_samples 4                 // number of rays per pixel for sampling
// focal_point < 0, 0, 0 >        // point that is in focus <x,y,z>
// confidence 0.9                 // [0...1] when to move on while sampling (smaller is less accurate)
// variance 1/128                 // [0...1] how precise to calculate (smaller is more accurate)
        
// (---spherical camera---)       // note that a sphere in this case is 360 by 180 degrees
// h_angle 360                    // horizontal field of view (in degrees and...)
// v_angle 180                    // vertical field of view (...are aspect ratios)
}
