Editing Dynamic range (section)

==Human perception==
{| class="wikitable floatright" style="width:auto; line-height:1.5em; text-align:right;"
|+ Power ratios and their equivalent decibels and stops (integer values in bold)
|-
! scope="col" | Factor (power)
! scope="col" | Decibels<br />({{math|10×log{{sub|10}} power}})
! scope="col" | Stops<br />({{math|log{{sub|2}} power}})
|-
|'''1''' ||   '''0''' ||  '''0'''
|-
|'''2''' ||      3.01 ||  '''1'''
|-
|3.16||   '''5''' ||     1.66
|-
|'''4''' ||      6.02 ||  '''2'''
|-
|'''5''' ||      6.99 ||     2.32
|-
|'''8''' ||      9.03 ||  '''3'''
|-
|'''10''' ||  '''10''' ||     3.32
|-
|'''16''' ||     12.0  ||  '''4'''
|-
|'''20''' ||     13.0  ||     4.32
|-
|31.6||  '''15''' ||     4.98
|-
|'''32'''||     15.1  ||  '''5'''
|-
|'''50''' ||     17.0  ||     5.64
|-
|'''100''' ||  '''20''' ||     6.64
|-
|'''1,000''' ||  '''30''' ||     9.97 
|-
|'''1,024''' ||     30.1  || '''10'''
|-
|'''10,000''' ||  '''40''' ||    13.3 
|- 
|'''100,000''' ||  '''50''' ||    16.6
|- 
|'''1,000,000''' ||  '''60''' ||    19.9
|- 
|'''1,048,576''' ||     60.2  || '''20'''
|-
|'''100,000,000''' ||  '''80''' ||    26.6 
|- 
|'''1,073,741,824''' ||     90.3  || '''30'''
|-
|'''10,000,000,000''' || '''100''' ||    33.2
|}
The human senses of [[sight]] and [[hearing]] have a relatively high dynamic range. However, a human cannot perform these feats of perception at both extremes of the scale at the same time. The human eye takes time to adjust to different light levels, and its dynamic range in a given scene is actually quite limited due to optical [[glare (vision)|glare]]. The instantaneous dynamic range of human audio perception is similarly subject to [[Auditory masking|masking]] so that, for example, a whisper cannot be heard in loud surroundings.

A human is capable of hearing (and usefully discerning) anything from a quiet murmur in a [[soundproofing|soundproofed]] room to the loudest heavy metal concert. Such a difference can exceed 100&nbsp;[[Decibel|dB]] which represents a factor of 100,000 in [[amplitude]] and a factor 10,000,000,000 in power.<ref>{{cite web|url=http://media.paisley.ac.uk/~campbell/AASP/Aspects%20of%20Human%20Hearing.PDF |title=Aspects of Human Hearing |author=D. R. Campbell |quote=The dynamic range of human hearing is [approximately] 120&nbsp;dB |access-date=2011-04-21 |url-status=dead |archive-url=https://web.archive.org/web/20110821051130/http://media.paisley.ac.uk/~campbell/AASP/Aspects%20of%20Human%20Hearing.PDF |archive-date=2011-08-21 }}</ref><ref>{{cite web |url=http://hyperphysics.phy-astr.gsu.edu/hbase/sound/earsens.html#c2 |quote=The practical dynamic range could be said to be from the threshold of hearing to the threshold of pain [130&nbsp;dB] |title=Sensitivity of Human Ear |access-date=2011-04-21 |url-status=live |archive-url=https://web.archive.org/web/20110604105752/http://hyperphysics.phy-astr.gsu.edu/hbase/sound/earsens.html#c2 |archive-date=2011-06-04}}</ref> The dynamic range of human hearing is roughly 140&nbsp;dB,<ref name="HuberRunstein513"/><ref>{{cite journal |url=https://www.cdc.gov/niosh/docs/98-126/ |title=Occupational Noise Exposure, CDC DHHS (NIOSH) Publication Number 98-126 |url-status=live |archive-url=https://web.archive.org/web/20170713151526/https://www.cdc.gov/niosh/docs/98-126/ |archive-date=2017-07-13 |doi=10.26616/NIOSHPUB98126 |year=1998 |doi-access=free |url-access=subscription }}</ref> varying with frequency,<ref name=":0">{{Cite web|url=https://people.xiph.org/~xiphmont/demo/neil-young.html|title=24/192 Music Downloads ...and why they make no sense|last=Montgomery|first=Christopher|website=xiph.org|access-date=2022-05-10|quote=The very quietest perceptible sound is about -8dbSPL|archive-date=2020-04-26|archive-url=https://web.archive.org/web/20200426050432/https://people.xiph.org/~xiphmont/demo/neil-young.html|url-status=dead}}</ref> from the [[threshold of hearing]] (around −9&nbsp;dB SPL<ref name=":0"/><ref>{{Cite web|url=http://www.ucl.ac.uk/~smgxprj/public/askscience_v1_8.pdf|title=What's the quietest sound a human can hear?|last=Jones|first=Pete R|date=November 20, 2014|publisher=University College London|access-date=2016-03-16|quote=On the other hand, you can also see in Figure 1 that our hearing is slightly more sensitive to frequencies just above 1 kHz, where thresholds can be as low as −9&nbsp;dB SPL!|url-status=live|archive-url=https://web.archive.org/web/20160324102019/http://www.ucl.ac.uk/~smgxprj/public/askscience_v1_8.pdf|archive-date=March 24, 2016}}</ref><ref>{{Cite web|url=http://www.feilding.net/sfuad/musi3012-01/html/lectures/007_hearing_II.htm|title=Lecture 007 Hearing II|last=Feilding|first=Charles|website=College of Santa Fe Auditory Theory|access-date=2016-03-17|quote=The peak sensitivities shown in this figure are equivalent to a sound pressure amplitude in the sound wave of 10 μPa or: about -6&nbsp;dB (SPL). Note that this is for monaural listening to a sound presented at the front of the listener. For sounds presented on the listening side of the head there is a rise in peak sensitivity of about 6&nbsp;dB [−12&nbsp;dB SPL] due to the increase in pressure caused by reflection from the head.|url-status=dead|archive-url=https://web.archive.org/web/20160507181640/http://www.feilding.net/sfuad/musi3012-01/html/lectures/007_hearing_II.htm|archive-date=2016-05-07}}</ref> at 3&nbsp;kHz) to the [[threshold of pain]] (from 120 to 140&nbsp;dB SPL<ref>{{Cite book|title=American Institute of Physics handbook|last=Newman|first=Edwin B.|date=1972-01-01|publisher=McGraw-Hill|isbn=978-0070014855|location=New York|pages=3–155|language=en|chapter=Speech and Hearing|quote=The upper limit for a tolerable intensity of sound rises substantially with increasing habituation. Moreover, a variety of subjective effects are reported, such as discomfort, tickle, pressure, and pain, each at a slightly different level. As a simple engineering estimate it can be said that naive listeners reach a limit at about 125&nbsp;dB SPL and experienced listeners at 135 to 140&nbsp;dB.|oclc = 484327}}</ref><ref name="painthres"/><ref name="dictionary"/>).  This wide dynamic range cannot be perceived all at once, however; the [[tensor tympani]], [[stapedius muscle]], and [[outer hair cells]] all act as mechanical [[dynamic range compressor]]s to adjust the sensitivity of the ear to different ambient levels.<ref>{{Cite web|url=https://www.soundonsound.com/sos/mar11/articles/how-the-ear-works.htm|title=How The Ear Works|website=www.soundonsound.com|access-date=2016-03-18|url-status=live|archive-url=https://web.archive.org/web/20150606112017/http://www.soundonsound.com/sos/mar11/articles/how-the-ear-works.htm|archive-date=2015-06-06}}</ref>

A human can see objects in [[starlight]]{{efn|[[Color vision|Colour differentiation]] is reduced at low light levels.}} or in bright [[sunlight]], even though on a moonless night objects receive one billionth (10<sup>−9</sup>) of the illumination they would on a bright sunny day; a dynamic range of 90&nbsp;dB. Change of sensitivity is achieved in part through adjustments of the iris and slow chemical changes, which take some time.

In practice, it is difficult for humans to achieve the full dynamic experience using electronic equipment. For example, a good quality [[liquid-crystal display]] (LCD) has a dynamic range limited to around 1000:1,{{efn|Commercially the dynamic range is often called the [[contrast ratio]] meaning the full-on to full-off [[luminance]] ratio.}} and some of the latest [[CMOS]] image sensors now{{When|date=July 2019}} have measured dynamic ranges of about 23,000:1.<ref>{{cite web |url=http://www.dxomark.com/index.php/eng/DxOMark-Sensor |title=DXOmark Sensor Ranking |access-date=2015-06-12 |url-status=dead |archive-url=https://web.archive.org/web/20100505035657/http://www.dxomark.com/index.php/eng/DxOMark-Sensor |archive-date=2010-05-05 }}</ref>{{efn|Reported as 14.5 [[Stops (Dynamic Range)|stop]]s, or doublings, equivalent to [[binary digit]]s.}}  Paper reflectance can produce a dynamic range of about 100:1.<ref>{{cite web |url = http://www.cambridgeincolour.com/tutorials/dynamic-range.htm |title = Dynamic Range in Digital Photography |access-date = 2011-07-11 |url-status = live |archive-url = https://web.archive.org/web/20110717103219/http://www.cambridgeincolour.com/tutorials/dynamic-range.htm |archive-date = 2011-07-17}}</ref> A [[professional video camera]] such as the Sony Digital Betacam achieves a dynamic range of greater than 90&nbsp;dB in audio recording.<ref>{{cite web |url=http://pro.sony.com/bbsc/ssr/cat-videorecorders/cat-recmpegimx/product-MSWM2100%2F1/ |title=Sony Product Detail Page MSWM2100/1 |publisher=Sony Pro |access-date=2011-12-30 |url-status=dead |archive-url=https://web.archive.org/web/20120229205150/http://pro.sony.com/bbsc/ssr/cat-videorecorders/cat-recmpegimx/product-MSWM2100%2F1/ |archive-date=2012-02-29 }}</ref>