In the rug/lens example this would require placing the focus plane slightly above and parallel to the rug with a small aperture.ĭeciding where to optimally place the focus plane can become a tricky game of geometry, particularly if the subject traverses both front/back and up/down directions. This type of placement is common for many types of flower shots, since these have a geometry similar to this rug/lens example.įor landscapes and architecture, however, the goal is usually to achieve maximal sharpness throughout. Also note how the field of view has moved downward due to the tilt, which should be taken into account.Īnother possibility would be to place the depth of field both above and parallel to the rug, such that only the tops of the two lenses are in sharp focus (right image). This is because the focus plane is at an angle in between the rug and lens. Note how both the rug and vertical depth of field appear to have decreased. This can be particularly useful for portraits when a wide aperture is insufficient, or when one wishes to focus on only part of a vertical object. Tilt can also be used to reduce apparent depth of field, as demonstrated by the 8° upward tilt image. Each image is taken using a wide aperture of f/2.8 to make the depth of field more noticeable at this small image size. The example below demonstrates the effect of tilt movements on a scene whose subject matter traverses both up/down and front/back directions. Tilt movements can sometimes avoid this technical limitation by making more efficient use of the depth of field, depending on the subject matter. The problem is that one could use even smaller apertures to increase depth of field, but not without also increasing softness at the camera's focus plane due to diffraction. TILT MOVEMENTS TO REPOSITION DEPTH OF FIELDĭepth of field for many scenes is often insufficient using standard equipment-even with small lens apertures. Also note that for the sake of brevity, the rest of this tutorial will use "plane of sharpest focus" and "focus plane" synonymously. The focusing distance can also change the plane of sharpest focus along with tilt, and will be discussed later in this tutorial.
Notice that even a small lens tilt angle can produce a correspondingly large tilt in the plane of sharpest focus. Try experimenting with different values of tilt to get a feel for how this influences the plane of sharpest focus. Purple line ( -) represents plane parallel to lens plane and separated by the lens focal length. When the Scheimpflug principle is combined with the "Hinge" or "Pivot Rule," these collectively define the location for the plane of sharpest focus as follows:įigure based on actual calculations using Canon's 45 mm TS-E lens vertical scale compressed 2X. In the diagram below, this intersection is actually a point since the line is perpendicular to your the screen. The Scheimpflug principle states that the sensor plane, lens plane and plane of sharpest focus must all intersect along a line. CONCEPT: SCHEIMPFLUG PRINCIPLE & HINGE RULE The tilt effect therefore does not necessarily increase depth of field-it just allows the photographer to customize its location to better suit their subject matter.
This produces a wedge-shaped depth of field whose width increases farther from the camera. Tilt movements enable the photographer to tilt the plane of sharpest focus so that it no longer lies perpendicular to the lens axis. This means that the lens's center of perspective no longer corresponds the the image's center of perspective, and produces an effect similar to only using a crop from the side of a correspondingly wider angle lens. Shift movements enable the photographer to shift the location of the lens's imaging circle relative to the digital camera sensor.
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