Editing Metering mode (section)

===Multi-zone metering===
[[File:Multizone metering example.jpg|thumb|Honeycomb Metering on a Dynax 5D. The AF point was set to the eye of the toy; the camera has been able to produce a good exposure, by not being fooled by the strong back lighting of the out of focus areas.]]

This mode is also called ''matrix'', ''evaluative'', ''honeycomb'', ''segment metering'', or ''esp'' (electro selective pattern) metering on some cameras. This metering mode was first introduced by the [[Nikon FA]] and was termed Automatic Multi-Pattern metering. On a number of cameras this is the default or standard setting. The camera measures the light intensity in several points in the scene and then combines the results to find the setting for the best exposure. The method of calculation can be different from camera to camera. The actual number of ''zones'' used varies widely, from several to over a thousand. The design concept behind multi-zone is to reduce the need to use [[exposure compensation]].<ref>[http://www.canon.com/technology/canon_tech/explanation/multi_zone.html Canon technology description for evaluative metering.] {{webarchive |url=https://web.archive.org/web/20070522003526/http://www.canon.com/technology/canon_tech/explanation/multi_zone.html |date=May 22, 2007 }}</ref>

Many manufacturers keep their exact calculation methods confidential as proprietary information. A number of factors are taken into consideration, including:
[[autofocus]] point, distance to subject, areas in or out of focus, colours/hues of the scene, and backlighting. Multi-zone tends to bias its exposure towards the autofocus point, thus ensuring that the point of interest has been exposed for properly. A database of thousands of exposures may be pre-stored in the camera, and the processor can use that information to determine what is being photographed.<ref>{{cite web | publisher = Nikon Corporation | title = Exposure Metering | url = http://imaging.nikon.com/products/imaging/technology/scene/14/index.htm | url-status = dead | archive-url = https://web.archive.org/web/20100428034831/http://imaging.nikon.com/products/imaging/technology/scene/14/index.htm | archive-date = 2010-04-28 }}</ref>

Some cameras allow the option of locking exposure when autofocus is achieved. In other cameras the AF point is not used for exposure calculation, and in such cases it is common for metering to default to a central point in the viewfinder, using a pattern based on that area. There is considerable variation among different manufacturers how multi-zone metering is implemented–even in the model range of the same brand–and how much priority is given to the AF point itself. Some "Scene" modes, such as sunset, sports and night exposures also often affect the calculations of this metering pattern.