Pixel shift is a method in digital cameras for producing a super resolution image. The method works by taking several images, after each such capture moving (“shifting”) the sensor to a new position. In digital colour cameras that employ pixel shift, this avoids a major limitation inherent in using Bayer pattern for obtaining colour, and instead produces an image with increased colour resolution and, assuming a static subject or additional computational steps, an image free of colour moiré. Taking this idea further, sub-pixel shifting may increase the resolution of the final image beyond that suggested by the specified resolution of the image sensor. [Wikipedia]
For example, my camera contains a 102 Mpixel sensor. A sequence of 16 images shifted by half a pixel are merged into a 400 Mpixel image. In the example below, the original image measured 23,264 x 17,448 pixels. I cropped it to the framed area of the petit point picture, which measured 18,249 x 15,394 pixels (figure 1). I then cropped an area to 100%, measuring 3,166 x 2,131 pixels (figure 2).
The constraint on this process is that neither the camera nor the subject can move between the 16 shots. A tripod manages movement of the camera. Movement is not a problem if the subject is still life photography. One might be lucky, on a windless day, with landscape work as well. In the circumstances where the technique is workable, the ability to “zoom in” provides an alternative, or a complement, to macro work.
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