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In{{Short [[photography]], the '''metering mode''' refers to the waydescription|Way in which a [[camera]] determines the [[exposure (photography)|exposure]].}}
In [[photography]], the '''metering mode''' refers to the way in which a [[camera]] determines [[exposure (photography)|exposure]]. Cameras generally allow the user to select between ''spot'', ''center-weighted average'', or ''multi-zone'' metering modes. The different metering modes allow the user to select the most appropriate one for use in a variety of lighting conditions. In complex light situations professional photographers tend to switch to manual mode, rather than depending on a setting determined by the camera.
== =Examples Spotof metering =modes== ▼[[File:Metering-Digital.gif|thumb|Digital metering feedback]]
[[File:Metering.gif|thumb|Analog metering feedback ([[light meter]])]]
== Examples of=Spot metering modes ===
With spot metering, the camera will measure only a very small area of the scene (1–5% of the [[viewfinder]] area). By default this is the centre of the scene. The user can select a different off-centre spot or recompose by moving the camera after metering.
Cameras generally allow the user to select between ''spot'', ''center-weighted average'', or ''multi-zone'' metering modes.
Certain models support a mode which allows averaging of multiple spot meter readings, and some support metering of highlight and shadow areas.
Spot metering is very accurate and is not influenced by other areas in the frame. It is commonly used to shoot very high contrast scenes. For example, ifin thea subject'sbacklit backsituation isa beingrising hitsun bymay thebe risingbehind suna andperson thewhose face iswill abe lotmuch darker than the bright halo around the subject's backbody and hairline . (the subject is "backlit"), spotSpot metering allows the photographercamera to measure the light bouncingreflected offfrom the subjectperson's face and expose properly for that, instead of adjusting exposure for the much brighter light around the hairline. TheWith the face properly exposed, the area around the back and hairline will then become over-exposed. SpotIn many cases spot metering iswill over or underexpose a methodportion uponof whichthe scene, so that the [[Zonepoint System]]of dependsinterest will be correctly exposed. ▼Various metering modes are provided to allow the user to select the most appropriate one for use in a variety of lighting conditions.
Another example of the use of spot metering is photographing the moon. Other metering methods will increase overall exposure in an attempt to lighten the dark sky area, resulting in overexposure of the moon. Spot metering gives correct exposure of the moon and underexposes the rest of the scene which was dark already, so the low exposure is not noticeable. Spot metering may also be used for theatre photography, where brightly lit actors appear in a darkened auditorium. Spot metering is a method upon which the [[Zone System]] depends.
With spot metering, the camera will only measure a very small area of the scene (between 1-5% of the viewfinder area). This will typically be the very centre of the scene, but some cameras allow the user to select a different off-centre spot, or to recompose by moving the camera after metering. The first spot meter was built by [[Arthur James Dalladay]], editor of The [[British Journal of Photography]] in about 1935 and described it in the BJP Almanac of 1937 on pages 127 to 138.<ref>{{cite web|url=http://www.shutterbug.net/techniques/lighting/1002sb_thesei/|title=The SEI Photometer A Legend Among Spot Meters|last=Hicks|first=Roger W.|date=October 2002|publisher=Shutterbug Magazine|accessdate=15 December 2009}}</ref>
=== Center-weighted Averageaverage metering === ▼A few models (including the [[Olympus OM-4]], [[Canon T90]] and in the digital world, the [[Olympus C-5050z]]) support a ''Multi-Spot'' mode which allows multiple spot meter readings to be taken of a scene that are averaged. Some cameras, the OM-4 and T90 included, also support metering of highlight and shadow areas.
In this system, the meter concentrates on the central 60–80% of the scene. The balance is then "[[feathering|feathered]]" out towards the edges. This mode of exposure is less influenced by peripheral areas of the scene and is therefore well suited for photographs with subjects or objects of interest in the central part of the image. Some cameras allow the user to adjust the weight/balance of the central portion to the peripheral one. If the camera allows a user to move the focus point off the image center, metering will occur around the new focus location. Although promoted as a feature, center-weighted metering was originally a consequence of the meter reading from the focusing screen of [[SLR camera]]s. Light scatter from the focusing screen and proximity of the meter cell caused less sensitivity at the edges.
=== PartialAverage metering === ▼▲Spot metering is very accurate and is not influenced by other areas in the frame. It is commonly used to shoot very high contrast scenes. For example, if the subject's back is being hit by the rising sun and the face is a lot darker than the bright halo around the subject's back and hairline (the subject is "backlit"), spot metering allows the photographer to measure the light bouncing off the subject's face and expose properly for that, instead of the much brighter light around the hairline. The area around the back and hairline will then become over-exposed. Spot metering is a method upon which the [[Zone System]] depends.
In this metering mode , the camera will use theuses light information coming from the entire scene and averagescreates an average for the final exposure setting, giving no weighting to any particular portion of the metered area . In some situations, such as a snowy landscape, this mode will result in underexposure by 2 [[f-number|f-stops]] or more, because the metering system attempts to darken an excessively bright scene. ▼
=== Partial Multi-zone(selective) metering === ▼Another example of spot metering usage would be when photographing the moon. Due to the very dark nature of the scene, other metering methods tend to overexpose the moon. Spot metering will allow for more detail to be brought out in the moon while underexposing the rest of the scene. More commonly, spot metering is used in theatre photography, where the brightly lit actors stand before a dark or even black curtain or scrim. Spot metering only considers the actors in this case, while ignoring the overall darkness of the scene.
This mode meters a larger area than spot metering (around 10 -–15% of the entire frame), and is generally used when very bright or very dark areas on the edges of the frame would otherwise unduly influence the metering unduly. LikeAs in spot metering, some cameras can use variable points to takefor readings from, (in general autofocus points), or haveuse a fixed point in the centre of the viewfinder. Partial metering is found mostly on Canon cameras.▼
=== CenterMulti-weighted averagezone metering ===
In this system, the meter concentrates between 60 to 80 percent of the sensitivity towards the central part of the viewfinder. The balance is then "feathered" out towards the edges. Some cameras will allow the user to adjust the weight/balance of the central portion to the peripheral one. One advantage of this method is that it is less influenced by small areas that vary greatly in brightness at the edges of the viewfinder; as many subjects are in the central part of the frame, consistent results can be obtained.
▲=== Average metering ===
▲In this metering mode the camera will use the light information coming from the entire scene and averages for the final exposure setting, giving no weighting to any particular portion of the metered area.
▲This mode meters a larger area than spot metering (around 10-15% of the entire frame), and is generally used when very bright or very dark areas on the edges of the frame would otherwise influence the metering unduly. Like spot metering, some cameras can use variable points to take readings from, (in general autofocus points), or have a fixed point in the centre of the viewfinder. Partial metering is found mostly on Canon cameras.
▲=== 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]], where it was called Automatic Multi-Pattern metering. On a number of cameras this is the default/standard metering setting. Here the camera measures the light intensity in several points in the scene, and then combines the results to find the settings for the best exposure. How they are combined/calculated deviates from camera to camera. The actual number of ''zones'' used varies wildly, from several to over a thousand. However performance should not be concluded on the number of zones alone, or the layout. In general, the most advanced metering is found on [[single-lens reflex]] cameras. ▼
▲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]] , where itand was calledtermed Automatic Multi-Pattern metering. On a number of cameras this is the default / or standard metering setting. Here theThe camera measures the light intensity in several points in the scene , and then combines the results to find the settingssetting for the best exposure. HowThe theymethod areof combined/calculatedcalculation can be deviatesdifferent from camera to camera. The actual number of ''zones'' used varies wildlywidely, from several to over a thousand. HoweverThe performancedesign shouldconcept notbehind bemulti-zone concludedis to onreduce the numberneed ofto zonesuse alone, or[[exposure the layoutcompensation]]. <ref>[http://www.canon.com/technology/canon_tech/explanation/multi_zone.html InCanon general,technology thedescription mostfor advancedevaluative metering .] is{{webarchive found|url=https://web.archive.org/web/20070522003526/http://www.canon.com/technology/canon_tech/explanation/multi_zone.html on|date=May [[single-lens22, reflex]]2007 cameras.}}</ref>
Many manufacturers are less than open about the exact calculations used to determine the exposure. A number of factors are taken into consideration, including the following: ▼[[Autofocus]] point, distance to subject, areas in focus or out of focus, colours/hues of the scene, and backlighting. Multi-zone tends to bias its exposure towards the autofocus point being used (whilst taking into account other areas of the frame too), thus ensuring that the point of interest has been exposed for properly, (this often means the subject area being exposed for as a mid-tone). A database of many thousands of exposures is pre-stored in the camera, and the processor can use a ''selective pattern'' 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}}</ref> ▼
▲Many manufacturers are less than open aboutkeep thetheir exact calculationscalculation usedmethods toconfidential determineas theproprietary exposureinformation. A number of factors are taken into consideration, including the following:
Some cameras allow the user to link or unlink the autofocus and metering, and allow the option of locking exposure once AF confirmation is achieved, ''AEL'', (auto-exposure lock). Using manual focus, and on many compacts/bridge cameras, the AF point is not used as part of the exposure calculation, in such instances it is common for the metering to default to a central point in the viewfinder, using a pattern based on that area. There is considerable variation from different manufacturers as to how multi-zone metering is implemented, and even from the same maker in their model range, and how much "priority" is given to the AF point itself. Some "Scene" modes, such as sunset, sports, night exposures etc., also often affect the calculations of this metering pattern. ▼▲[[ Autofocusautofocus]] point, distance to subject, areas in focus or out of focus, colours/hues of the scene, and backlighting. Multi-zone tends to bias its exposure towards the autofocus point being used (whilst taking into account other areas of the frame too), thus ensuring that the point of interest has been exposed for properly , (this often means the subject area being exposed for as a mid-tone). A database of many thousands of exposures ismay be pre-stored in the camera, and the processor can use a ''selectivethat pattern''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 user to link or unlink the autofocus and metering, and allow the option of locking exposure oncewhen AF confirmationautofocus is achieved , ''AEL'', (auto-exposure lock). UsingIn manual focus, and on many compacts/bridgeother cameras , the AF point is not used as part of thefor exposure calculation, and in such instancescases it is common for the metering to default to a central point in the viewfinder, using a pattern based on that area. There is considerable variation fromamong different manufacturers as to how multi-zone metering is implemented,implemented–even and even fromin the samemodel makerrange inof theirthe modelsame range, andbrand–and how much "priority " is given to the AF point itself. Some "Scene" modes, such as sunset, sports , and night exposures etc., also often affect the calculations of this metering pattern.
However, some photographers may be uncomfortable with multi-zone metering. This tends to stem from a lack of clarity about "how" the camera reacts in certain situations. 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.]{{Dead link|url=http://www.canon.com/technology/canon_tech/explanation/multi_zone.html|date=January 2010}}</ref>
===Highlight-weighted metering===
Some users have problems making wide-angle shots with high contrast, due to the large area which can vary greatly in brightness. It is important to understand that even in this situation, the focus point can be critical to the overall exposure.
[[ Clippingclipping (photography)|Clipping]] is reduced by using a high resolution metering sensor and analyzing each area for washed-out ("blown ") highlights or [[ Exposure_Exposure (photography)#Blacks|underexposed]] shadows.<ref> [{{cite web |url=http://photographylife.com/nikon-d810-announcement |title=Nikon D810 Announcement ] Photographylife|publisher=PhotographyLife}}</ref> Although there are some similarities with Multimulti-zone, Matrixmatrix, or evaluative metering, this mode uses a high -resolution sensor for detailed detection and gives more ''weight'' to reduce clipping . First used in the [[Nikon D810]].<ref> [{{cite web |url=http:// www.amateurphotographer.co.uk/reviews/dslrs/129531/1/first-look-review-nikon-d810 |title=First Look Review: Nikon D810 ] Amateurphotographer|publisher=[[Amateur Photographer]]}}</ref> ▼
==See also==
===Highlight Weighted Metering===
*[[Feathering]]
▲[[Clipping (photography)|Clipping]] is reduced by using a high resolution metering sensor and analyzing each area for blown highlights or [[Exposure_(photography)#Blacks|underexposed]] shadows.<ref>[http://photographylife.com/nikon-d810-announcement Nikon D810 Announcement] Photographylife</ref> Although there are some similarities with Multi-zone, Matrix or evaluative metering, this mode uses a high resolution sensor for detailed detection and gives more ''weight'' to reduce clipping. First used in the [[Nikon D810]].<ref>[http://www.amateurphotographer.co.uk/reviews/dslrs/129531/1/first-look-review-nikon-d810 First Look Review: Nikon D810] Amateurphotographer</ref>
*[[Vignetting]]
== References ==
{{reflist|date=December 2009}}
==External links==
* [https://photographylife.com/understanding-metering-modes Understanding Metering and Metering Modes]
* [http://www.dpreview.com/learn/?/Glossary/Exposure/Metering_01.htm Metering] in the [http://www.dpreview.com/ Digital Photography Review] glossary.
* [https://digital-photography-school.com/metering-modes-and-how-your-camera-meter-works/ Metering Modes and How Your Camera Meter Works]
* [http://nps.nikonimaging.com/technical_solutions/d810_tips/highlight/ Highlight-Weighted Metering: Technical Details and Use] Nikon
{{Photography}}
[[Category:PhotographyCamera equipmentfeatures]]
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