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class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-appearance.unpin">hide</button> </div> </div> </div> </nav> </div> </div> <div id="bodyContent" class="vector-body" aria-labelledby="firstHeading" data-mw-ve-target-container> <div class="vector-body-before-content"> <div class="mw-indicators"> </div> <div id="siteSub" class="noprint">From Wikipedia, the free encyclopedia</div> </div> <div id="contentSub"><div id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Perception of image sharpness which is unrelated to actual resolution</div> <figure typeof="mw:File/Frame"><a href="/wiki/File:Accutance.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/4/40/Accutance.svg/250px-Accutance.svg.png" decoding="async" width="250" height="250" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/40/Accutance.svg/375px-Accutance.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/40/Accutance.svg/500px-Accutance.svg.png 2x" data-file-width="250" data-file-height="250" /></a><figcaption>An image with artificially increased acutance</figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Usm-unsharp-mask.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/e/e6/Usm-unsharp-mask.png/220px-Usm-unsharp-mask.png" decoding="async" width="220" height="156" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/e6/Usm-unsharp-mask.png/330px-Usm-unsharp-mask.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/e6/Usm-unsharp-mask.png/440px-Usm-unsharp-mask.png 2x" data-file-width="3508" data-file-height="2480" /></a><figcaption>Another illustration, where <a href="/wiki/Overshoot_(signal)" title="Overshoot (signal)">overshoot</a> caused by using <a href="/wiki/Unsharp_masking" title="Unsharp masking">unsharp masking</a> to sharpen the image (bottom half) increases acutance.</figcaption></figure> <p>In <a href="/wiki/Photography" title="Photography">photography</a>, <b>acutance</b> describes a subjective perception of <a href="/wiki/Visual_acuity" title="Visual acuity">sharpness</a> that is related to the edge <a href="/wiki/Contrast_(vision)" title="Contrast (vision)">contrast</a> of an <a href="/wiki/Image" title="Image">image</a>.<sup id="cite_ref-Präkel2010_1-0" class="reference"><a href="#cite_note-Präkel2010-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Maître2015_2-0" class="reference"><a href="#cite_note-Maître2015-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> Acutance is related to the amplitude of the <a href="/wiki/Derivative" title="Derivative">derivative</a> of <a href="/wiki/Brightness" title="Brightness">brightness</a> with respect to space. Due to the nature of the <a href="/wiki/Human_visual_system" class="mw-redirect" title="Human visual system">human visual system</a>, an image with higher acutance appears sharper even though an increase in acutance does not increase real <a href="/wiki/Image_resolution" title="Image resolution">resolution</a>. </p><p>Historically, acutance was enhanced chemically during development of a <a href="/wiki/Negative_(photography)" title="Negative (photography)">negative</a> (high acutance developers), or by optical means in printing (<a href="/wiki/Unsharp_masking" title="Unsharp masking">unsharp masking</a>). In <a href="/wiki/Digital_photography" title="Digital photography">digital photography</a>, onboard camera software and image postprocessing tools such as <a href="/wiki/Adobe_Photoshop" title="Adobe Photoshop">Photoshop</a> or <a href="/wiki/GIMP" title="GIMP">GIMP</a> offer various sharpening facilities, the most widely used of which is known as "unsharp mask" because the algorithm is derived from the eponymous analog processing method. </p><p>In the example image, two light gray lines were drawn on a gray background. As the transition is instantaneous, the line is as sharp as can be represented at this resolution. Acutance in the left line was artificially increased by adding a one-pixel-wide darker border on the outside of the line and a one-pixel-wide brighter border on the inside of the line. The actual sharpness of the image is unchanged, but the apparent sharpness is increased because of the greater acutance. </p><p>Artificially increased acutance has drawbacks. In this somewhat overdone example most viewers will also be able to see the borders separately from the line, which create two halos around the line, one dark and one shimmering bright. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Tools">Tools</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Acutance&action=edit&section=1" title="Edit section: Tools"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Several image processing techniques, such as <a href="/wiki/Unsharp_masking" title="Unsharp masking">unsharp masking</a>, can increase the acutance in real images. </p> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Accutance_example.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/0/0b/Accutance_example.png/220px-Accutance_example.png" decoding="async" width="220" height="95" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/0/0b/Accutance_example.png/330px-Accutance_example.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/0/0b/Accutance_example.png/440px-Accutance_example.png 2x" data-file-width="600" data-file-height="260" /></a><figcaption>Unprocessed, slight unsharp masking, then strong unsharp masking.</figcaption></figure> <div class="mw-heading mw-heading3"><h3 id="Resampling">Resampling</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Acutance&action=edit&section=2" title="Edit section: Resampling"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Gibbs_phenomenon_10.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/d/de/Gibbs_phenomenon_10.png/220px-Gibbs_phenomenon_10.png" decoding="async" width="220" height="220" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/de/Gibbs_phenomenon_10.png/330px-Gibbs_phenomenon_10.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/d/de/Gibbs_phenomenon_10.png/440px-Gibbs_phenomenon_10.png 2x" data-file-width="570" data-file-height="570" /></a><figcaption><a href="/wiki/Low-pass_filter" title="Low-pass filter">Low-pass filtering</a> and <a href="/wiki/Resampling_(audio)" class="mw-redirect" title="Resampling (audio)">resampling</a> affect acutance.</figcaption></figure> <p><a href="/wiki/Low-pass_filter" title="Low-pass filter">Low-pass filtering</a> and resampling often cause <a href="/wiki/Overshoot_(signal)" title="Overshoot (signal)">overshoot</a>, which increases acutance, but can also reduce absolute gradient, which reduces acutance. Filtering and resampling can also cause <a href="/wiki/Clipping_(audio)" title="Clipping (audio)">clipping</a> and <a href="/wiki/Ringing_artifacts" title="Ringing artifacts">ringing artifacts</a>. An example is <a href="/wiki/Bicubic_interpolation" title="Bicubic interpolation">bicubic interpolation</a>, widely used in <a href="/wiki/Image_processing" class="mw-redirect" title="Image processing">image processing</a> for resizing images. </p> <div class="mw-heading mw-heading2"><h2 id="Definition">Definition</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Acutance&action=edit&section=3" title="Edit section: Definition"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>One definition of acutance is determined by imaging a sharp "knife-edge", producing an S-shaped distribution over a width W between maximum density D<sub>1</sub> and minimum density D<sub>2</sub> – steeper transitions yield higher acutance. </p><p>Summing the slope G<sub>n</sub> of the curve at N points within W gives the acutance value A, </p><p><span class="mwe-math-element"><span class="mwe-math-mathml-display mwe-math-mathml-a11y" style="display: none;"><math display="block" xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A=\left(D_{1}-D_{2}\right){\frac {1}{N}}\sum _{n=1}^{N}G_{n}^{2}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mrow> <mo>(</mo> <mrow> <msub> <mi>D</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>1</mn> </mrow> </msub> <mo>−</mo> <msub> <mi>D</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> <mo>)</mo> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mn>1</mn> <mi>N</mi> </mfrac> </mrow> <munderover> <mo>∑</mo> <mrow class="MJX-TeXAtom-ORD"> <mi>n</mi> <mo>=</mo> <mn>1</mn> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mi>N</mi> </mrow> </munderover> <msubsup> <mi>G</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>n</mi> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msubsup> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A=\left(D_{1}-D_{2}\right){\frac {1}{N}}\sum _{n=1}^{N}G_{n}^{2}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/086d8836c53bf77462ae9217cc0a6f430b3723a1" class="mwe-math-fallback-image-display mw-invert skin-invert" aria-hidden="true" style="vertical-align: -3.005ex; width:25.909ex; height:7.343ex;" alt="{\displaystyle A=\left(D_{1}-D_{2}\right){\frac {1}{N}}\sum _{n=1}^{N}G_{n}^{2}}"></span> </p><p>More generally, the acutance at a point in an image is related to the <a href="/wiki/Image_gradient" title="Image gradient">image gradient</a>, the <a href="/wiki/Spatial_gradient" title="Spatial gradient">gradient</a> of the density (or intensity) at that point, a vector quantity: </p><p><span class="mwe-math-element"><span class="mwe-math-mathml-display mwe-math-mathml-a11y" style="display: none;"><math display="block" xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A=\nabla D}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mi mathvariant="normal">∇</mi> <mi>D</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A=\nabla D}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/c64377cb3ea7a2b1e295be81eb1108e7b3eee73a" class="mwe-math-fallback-image-display mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:8.702ex; height:2.176ex;" alt="{\displaystyle A=\nabla D}"></span> </p><p>Several <a href="/wiki/Edge_detection" title="Edge detection">edge detection</a> algorithms exist, based on the gradient norm or its components. </p> <div class="mw-heading mw-heading2"><h2 id="Sharpness">Sharpness</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Acutance&action=edit&section=4" title="Edit section: Sharpness"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Perceived sharpness is a combination of both <a href="/wiki/Optical_resolution" title="Optical resolution">resolution</a> and acutance: it is thus a combination of the captured resolution, which cannot be changed in processing, and of acutance, which can be so changed. </p><p>Properly, perceived sharpness is the steepness of transitions (slope), which is change in output value divided by change in position – hence it is maximized for large changes in output value (as in sharpening filters) and small changes in position (high resolution). </p><p>Coarse <a href="/wiki/Film_grain" title="Film grain">grain</a> or <a href="/wiki/Image_noise" title="Image noise">noise</a> can, like sharpening filters, increase acutance, hence increasing the perception of sharpness, even though they degrade the <a href="/wiki/Signal-to-noise_ratio" title="Signal-to-noise ratio">signal-to-noise ratio</a>. </p><p>The term <i><style data-mw-deduplicate="TemplateStyles:r1238216509">.mw-parser-output .vanchor>:target~.vanchor-text{background-color:#b1d2ff}@media screen{html.skin-theme-clientpref-night .mw-parser-output .vanchor>:target~.vanchor-text{background-color:#0f4dc9}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .vanchor>:target~.vanchor-text{background-color:#0f4dc9}}</style><span class="vanchor"><span id="critical_sharpness"></span><span class="vanchor-text">critical sharpness</span></span></i> is sometimes heard (by analogy with <a href="/wiki/Critical_focus" title="Critical focus">critical focus</a>) for "obtaining maximal optical resolution", as limited by the <a href="/wiki/Sensor" title="Sensor">sensor</a>/<a href="/wiki/Film" title="Film">film</a> and <a href="/wiki/Lens" title="Lens">lens</a>, and in practice means minimizing <a href="/wiki/Camera_shake" class="mw-redirect" title="Camera shake">camera shake</a> – using a <a href="/wiki/Tripod_(photography)" title="Tripod (photography)">tripod</a> or alternative support, <a href="/wiki/Mirror_lock-up" title="Mirror lock-up">mirror lock-up</a>, a <a href="/wiki/Cable_release" class="mw-redirect" title="Cable release">cable release</a> or timer, <a href="/wiki/Image_stabilization" title="Image stabilization">image stabilizing</a> lenses – and <a href="/wiki/Optimal_aperture" class="mw-redirect" title="Optimal aperture">optimal aperture</a> for the lens and scene, usually 2–3 stops down from wide-open (more for deeper scenes: balances off diffraction blur with defocus blur or lens limits at wide-open). </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Acutance&action=edit&section=5" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Contrast_(vision)" title="Contrast (vision)">Contrast (vision)</a></li> <li><a href="/wiki/Cornsweet_illusion" title="Cornsweet illusion">Cornsweet illusion</a></li> <li><a href="/wiki/Edge_enhancement" title="Edge enhancement">Edge enhancement</a></li> <li><a href="/wiki/Mach_bands" title="Mach bands">Mach bands</a></li> <li><a href="/wiki/Ringing_artifact" class="mw-redirect" title="Ringing artifact">Ringing artifact</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Acutance&action=edit&section=6" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-Präkel2010-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-Präkel2010_1-0">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFDavid_Präkel2010" class="citation book cs1">David Präkel (4 January 2010). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=f7X5vYbUd0sC&pg=PA19"><i>The Visual Dictionary of Photography</i></a>. AVA Publishing. pp. 19–. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-2-940411-04-7" title="Special:BookSources/978-2-940411-04-7"><bdi>978-2-940411-04-7</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=The+Visual+Dictionary+of+Photography&rft.pages=19-&rft.pub=AVA+Publishing&rft.date=2010-01-04&rft.isbn=978-2-940411-04-7&rft.au=David+Pr%C3%A4kel&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3Df7X5vYbUd0sC%26pg%3DPA19&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAcutance" class="Z3988"></span></span> </li> <li id="cite_note-Maître2015-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-Maître2015_2-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMaître2015" class="citation book cs1">Maître, Henri (2015). "Image Quality". <i>From Photon to Pixel</i>. pp. 205–251. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1002%2F9781119238447.ch6">10.1002/9781119238447.ch6</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/9781119238447" title="Special:BookSources/9781119238447"><bdi>9781119238447</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=Image+Quality&rft.btitle=From+Photon+to+Pixel&rft.pages=205-251&rft.date=2015&rft_id=info%3Adoi%2F10.1002%2F9781119238447.ch6&rft.isbn=9781119238447&rft.aulast=Ma%C3%AEtre&rft.aufirst=Henri&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAcutance" class="Z3988"></span></span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="Further_reading">Further reading</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Acutance&action=edit&section=7" title="Edit section: Further reading"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><i>The Focal Encyclopedia of Photography</i>, Focal Press, 1956, Ed. Frederick Purves</li></ul> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Acutance&action=edit&section=8" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a rel="nofollow" class="external text" href="http://www.cambridgeincolour.com/tutorials/sharpness.htm">Tutorials: Sharpness</a>, at Cambridge in Colour</li> <li><a rel="nofollow" class="external text" href="http://www.luminous-landscape.com/tutorials/sharp.shtml">Lens Sharpness: The Never-Ending Quest</a>, at <a rel="nofollow" class="external text" href="http://www.luminous-landscape.com/">The Luminous Landscape</a></li></ul>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://en.wikipedia.org/w/index.php?title=Acutance&oldid=1179281093">https://en.wikipedia.org/w/index.php?title=Acutance&oldid=1179281093</a>"</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/Help:Category" title="Help:Category">Categories</a>: <ul><li><a href="/wiki/Category:Image_processing" title="Category:Image processing">Image processing</a></li><li><a href="/wiki/Category:Science_of_photography" title="Category:Science of photography">Science of photography</a></li></ul></div><div id="mw-hidden-catlinks" class="mw-hidden-catlinks mw-hidden-cats-hidden">Hidden categories: <ul><li><a href="/wiki/Category:Articles_with_short_description" title="Category:Articles with short description">Articles with short description</a></li><li><a href="/wiki/Category:Short_description_matches_Wikidata" title="Category:Short description matches Wikidata">Short description matches Wikidata</a></li></ul></div></div> </div> </main> </div> <div class="mw-footer-container"> <footer id="footer" class="mw-footer" > <ul id="footer-info"> <li id="footer-info-lastmod"> This page was last edited on 9 October 2023, at 02:42<span class="anonymous-show"> (UTC)</span>.</li> <li id="footer-info-copyright">Text is available under the <a href="/wiki/Wikipedia:Text_of_the_Creative_Commons_Attribution-ShareAlike_4.0_International_License" title="Wikipedia:Text of the Creative Commons Attribution-ShareAlike 4.0 International License">Creative Commons Attribution-ShareAlike 4.0 License</a>; additional terms may apply. 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