Library · Reference

Glossary

Terms used in the library and the calculator. The Turkish equivalent is given next to each term.

Accommodation Uyum: The focusing of the eye's lens to the distance being looked at. In stereoscopic viewing the eye focuses on the screen. See Vergence–accommodation conflict.
Anaglyph Anaglif: Display in which the left and right images are separated by color; viewed with red/cyan glasses. Simple, but it distorts colors. See How stereoscopy works.
Angular parallax (angular disparity) Açısal paralaks: The difference between the vergence angle to the two images and the vergence angle to the screen. Approximately P / V radians. A commonly used comfort limit is 1°. See Parallax, Comfort zones.
Aperture (f-number) Diyafram: The light opening of the lens; given by the f-number (N): the ratio of the focal length to the entrance pupil diameter. As N increases, the opening gets smaller and the depth of field gets wider.
Arcminute Açı dakikası: One sixtieth of a degree: 1° = 60′. Small angles such as vertical parallax are given in this unit.
Cardboarding (cardboard effect) Karton etkisi: Objects look flat, like cut-out cardboard layers. It becomes more noticeable as roundness drops; below 0.2 is a commonly used limit (Mendiburu). See Cardboarding.
Circle of confusion Bulanıklık dairesi: The largest blur diameter on the sensor at which a point is still considered sharp. It sets the limits of the depth of field. By default the calculator uses 1/1500 of the sensor diagonal.
Comfort window Konfor penceresi: The parallax range the viewer can fuse without fatigue. It is the narrowest of the depth budget, the divergence limit and the angular parallax limit. See Comfort zones.
Converged rig (toe-in) Yakınsak düzen: Rig in which the cameras are rotated toward each other by equal angles; their central rays intersect at the convergence distance. The toe-in angle of each camera is β = atan(b / 2C). See Converged rig.
Convergence Konverjans: The distance in the scene that falls at zero parallax (C). Everything at this distance appears on the screen plane. See Convergence.
Convergence point Yakınsak kesişim noktası: In a converged rig, the point where the central rays of the two cameras intersect. An object at this point appears on the screen plane; its distance from the rig is the convergence distance. In the Cerit Triangle it is the main subject; optical focus follows it by default and can be set separately on a robotic rig. See Cerit Triangle.
Depth budget Derinlik bütçesi: The largest parallax allowed in front of and behind the screen, as a fraction of image width. For example, in the Sky 3D specification back +2%, front −1%; in cinema back +1%, front −2%.
Depth consistency Derinlik tutarlılığı: The condition that roundness is 1: b / C = e / V. Objects near the screen plane appear with their natural proportions (Devernay and Beardsley). See Depth consistency.
Depth grading Derinlik derecelendirme: Adjusting the depth of shots in post-production, mainly with HIT, to the target screen and the edit. See Post-production and mastering.
Depth of field Alan derinliği: The range of distances that appears acceptably sharp in the image. It changes with aperture, focal length and focus distance. In the Cerit Triangle it is an aesthetic choice.
Depth plane curvature Derinlik düzlemi eğriliği: In a converged rig, points at the same distance get different parallax toward the edges of the frame; a flat surface is perceived as curved (Woods et al. 1993). See Depth plane curvature.
Depth range Derinlik aralığı: The parallax difference between the nearest and farthest points of the scene. It is directly proportional to the interaxial and independent of convergence. See Interaxial.
Diopter Diyoptri: The reciprocal of distance in meters (1/m). Used to compare the focus and vergence distances of the eye. See Vergence–accommodation conflict.
Diplopia (double vision) Çiftlenme: The eyes cannot fuse the two images into one and see the object double. "Excess diplopia" in the calculator is the case where a point is both in focus and outside the comfort window.
Disparity Disparite: The horizontal position difference of a point between the left and right images, on the sensor or in the image. Magnified to the screen, it becomes parallax.
Divergence Iraksama: Screen parallax exceeding the interocular distance. The lines of sight do not intersect; the eyes have to turn outward. It has no counterpart in nature and is a hard limit.
Floating window Kayan pencere: Masking the image edges to fix a window violation: the left of the left-eye image for the left edge, the right of the right-eye image for the right edge. See Zero parallax plane.
Focal length Odak uzaklığı: The value that sets the angle of view of the lens (f, mm). A small value means a wide angle, a large value a narrow angle (telephoto).
Frame magnification Çerçeve büyütmesi: The ratio of screen width to sensor width: M = Ws / Wc. Disparity on the sensor becomes screen parallax by this ratio.
Fusion Füzyon: The brain combining the left-eye and right-eye images into a single image. An image that cannot be fused is seen double.
Geometric correction (rectification) Geometrik düzeltme: Removing differences between the two images other than horizontal parallax (vertical offset, rotation, scale, keystone, distortion) in post-production.
HIT (horizontal image translation) HIT, yatay görüntü kaydırma: Shifting the left and right images horizontally in opposite directions. It changes all parallax by the same amount; the scene moves forward or back, and the depth range stays the same. See Post-production and mastering.
Hyperfocal distance Hiperfokal uzaklık: When the lens is focused at this distance, the in-focus range extends from half this distance to infinity. H = f² / (N · c) + f.
Hyperstereo Hiperstereo: An interaxial much larger than the interocular distance. The scene may look miniaturized, like a model.
Hypostereo Hipostereo: An interaxial much smaller than the interocular distance. The scene may look enlarged; common in macro shooting.
Image circle Görüntü dairesi: The circular area the lens illuminates on the sensor plane. The sensor must stay inside this circle when shifted, too. See Sensor shift.
In-focus range Net alan: The region between the near and far limits of the depth of field. In the Cerit Triangle the in-focus range limits are matched to the comfort window limits. See Cerit Triangle.
Interaxial (stereo base) Kamera aralığı: The distance between the optical centers of the two lenses (b). It is the main variable that sets the amount of depth. See Interaxial.
Interocular distance (IPD) Göz arası: The distance between the viewer's two pupils. The adult average is about 63 mm; 65 mm is often used in design. Not to be confused with the interaxial.
Keystone Yamuk bozulma: Vertical parallax that appears in the corners of the frame in a converged rig. In mastering it is corrected by rotating each image back about its own center. See Keystone.
Main subject Ana obje: The main object in the shot that the viewer is meant to look at. It is usually placed near the screen plane.
Mastering: Bringing the shot stereo images to their final form for the target screen: geometric corrections, keystone, HIT, floating window and target screen masters. See Post-production and mastering, Mastering calculator.
Mirror rig (beam splitter) Ayna rig: Rig in which the two cameras are placed at right angles to each other with a semi-transparent mirror. The interaxial can be smaller than the width of the camera bodies. See Mirror rig.
Optical focus (focus distance) Optik fokus: The distance at which the lens is focused. In stereoscopy it is a separate setting from convergence; in the Cerit Triangle it follows the convergence point by default.
Orthostereoscopy Ortostereoskopi: Reproducing the scene at its real sizes and distances. Its condition is Wconv / Ws = C / V = b / e (Devernay and Beardsley). See Orthostereoscopy.
Parallax Paralaks: The horizontal distance between the right-eye and left-eye images of a point on the screen. Positive parallax is behind the screen, negative parallax in front of it. See Parallax.
Parallel rig Paralel düzen: Rig in which the optical axes of the cameras are parallel. Convergence is set by sensor shift or by HIT in post-production. See Parallel rig.
Puppet-theater effect Kukla tiyatrosu etkisi: Objects look smaller than they are, like puppets. Woods et al. (1993) relate it to the combination of a wide interaxial and a long focal length. See Puppet-theater effect.
Rig: A device that carries two cameras together for stereoscopic shooting and is used to adjust the distance and angle between them. It can be side-by-side or mirror.
Roundness (shape ratio) Biçim oranı: The ratio of an object's perceived depth to its perceived width. Near the screen plane ρ = b · V / (C · e).
Sensor Sensör: The surface in the camera that records the image. Its width (Wc) appears directly in the formulas. Super 35 is about 24.9 × 18.7 mm.
Sensor shift Sensör kaydırma: Shifting the sensors horizontally to set convergence in a parallel rig. The shift of each sensor is h = f · b / 2C. See Sensor shift.
Sky 3D specification Sky 3D şartnamesi: BSkyB's 3D broadcast specification from 2010. It limits parallax to 2% of image width behind the screen and 1% in front of it.
Stereo pair Stereo çift: Two images taken at the same time, one for the left eye and one for the right.
Stereo window Stereo pencere: The screen frame perceived as a window opening onto the scene. Objects in front of it extend out of the window; those behind it appear beyond the window.
Stereographer Stereograf: The person who manages depth in stereoscopic shooting: chooses the interaxial and convergence according to the shot, the story and the target screen.
Stereoscopy (S3D) Stereoskopi: The technique of creating depth perception by showing a separate image to each eye. See How stereoscopy works.
T-stop: The aperture value measured by the light the lens actually transmits. Depth of field depends on the f-number: N = T · √t (t transmittance).
Toe-in angle β İç açı β: In a converged rig, the angle by which each camera is turned inward: β = atan(b / 2C). The angle between the two cameras is 2β.
Vergence Yakınsama: The two eyes, or two cameras, turning toward the same point. For cameras the term convergence is also used. See Convergence.
Vergence–accommodation conflict Yakınsama–uyum çatışması: The eyes have to keep their focus on the screen while their vergence is at a different distance. One of the main causes of fatigue in stereoscopic viewing (Shibata et al. 2011). See Vergence–accommodation conflict.
Vertical parallax Dikey paralaks: The vertical difference between the left and right images of a point. It carries no depth information and strains the eyes; about 15 arcminutes is a commonly cited acceptance limit. See Keystone.
Window violation Pencere ihlali: An object that appears in front of the screen touches a side edge of the frame. The frame looks as if it cuts the object in front of it.
Zero parallax plane (screen plane) Sıfır paralaks düzlemi: The plane at the convergence distance; it appears on the screen itself. See Zero parallax plane.