Exposing to the right

A normally exposed image and its histogram. Details in the flowers are already discernible but recovering the shadows in post-production will increase noise.
A normally exposed image and its histogram. Details in the flowers are already discernible but recovering the shadows in post-production will increase noise.
An image exposed to the right (+1 EV) and its histogram. Details in the shadows are already discernible and the flowers are fully recoverable in post-production.
An image exposed to the right (+1 EV) and its histogram. Details in the shadows are already discernible and the flowers are fully recoverable in post-production.

In digital photography, exposing to the right (ETTR) is the technique of adjusting the exposure of an image as high as possible at base ISO (without causing unwanted saturation) to collect the maximum amount of light and thus get the optimum performance out of the digital image sensor.[1][2][3][4]

The name derives from the resulting image histogram which, according to this technique, should be placed close to the right of its display. Advantages include greater tonal range in dark areas, greater signal-to-noise ratio (SNR),[5] fuller use of the colour gamut and greater latitude during post-production.

The direction of the relative adjustment to the camera's meter reading depends on the dynamic range (or contrast ratio) of the scene.[dubiousdiscuss] Typically, with low-contrast scenes, an increase in exposure over that indicated by the camera's meter will be required. When attempting a single-exposure of a high dynamic-range scene, a reduction in exposure from the meter's reading may be needed.[dubiousdiscuss] In the final analysis, however, the camera's meter is irrelevant to ETTR since the ETTR exposure is established, not by a meter reading, but by the camera's exposure indicators, the histogram and/or the highlight-clipping indicators (blinkies/zebras).

ETTR images requiring increased exposure may appear to be overexposed (too bright) when taken and must be correctly processed (normalized) to produce a photograph as envisaged. Care must be taken to avoid clipping within any colour channel, other than acceptable areas such as specular highlights.

The principle is also applied in film photography in order to maximize the negative's latitude and density and achieve richer blacks when the image is printed slightly down.

  1. ^ Reichmann, Michael (2003-07-31). "Expose (to the) Right – Maximizing S/N Ratio in Digital Photography". The Luminous Landscape. Archived from the original on 2015-02-09. Retrieved 2016-07-05.
  2. ^ Reichmann, Michael (August 2011). "Optimizing Exposure – Why Do Camera Makers Give Us 19th Century Exposures With Our 21st Century Cameras?". The Luminous Landscape. Archived from the original on 2015-02-13. Retrieved 2016-07-07.
  3. ^ Carnathan, Bryan. "Exposure Basics".
  4. ^ "Digital Exposure Techniques".
  5. ^ Martinec, Emil (2008). "Noise, Dynamic Range and Bit Depth in Digital SLRs". Retrieved 4 February 2014.

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