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13.2& &&&&&&&Digital&Lens&Optimizer&(DLO)&Syste m&
The!Digital!Lens!Optimizing!system!is!b uilt!into!the!EOS! R! camera! and! is!intended! to!implem ent!real-
time!c orre ction s!for!a!n um b er!of!optical! aberrations!and!distortions!encountered! over!a!wide! range!of!
shooting!conditions.!!Before!the!light!rays!reach!the!CMOS!image!sensor!they!pass!through!the!multi-
element!lens!and!various!filters!as!illustra te d !in!Figure!40.!!!!
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Figure&40! A$simplistic$rendition$of$the$path$of$the$light$ray$that$enter$the$lens$and$are$ultimately$
projected$on$to$the$camera$image$sensor$
A! point! light! source! that! travels! through! a! lens! system! encounters! numerous! aberrations! —! both!
monochromatic!and!chromatic!—!that!ten ds!to!spread! th at!light.!!!Th e!optical!scientists!speak!of!a!Point!
Spread!Function.!!!!However,! the!cumulative!effect!of!the!aberrations!is!to!create!a!range!of!shapes!in!
that!sprea d! fu nc tion !a nd ! th ey! a re! affe cte d! b y! the ! im age ! he ight! a nd ! by ! the !o p eration al! settin gs! o f! zoo m ,!
focus,!and!iris.!!!!!
There! are!two!basic!limitations! to!image!resolution! within!all! lenses!—!the! first!is!the!cu m ulative !effec t!
of! the! six! monochromatic! and! chromatic! aberrations! (termed! the! defocusing! distortions! and! which!
worsen!as!the!lens!aperture!approaches!maximum),!and!the!second! is!diffraction!(which!worsens!as!the!
lens!ape rtu re !is !st o pp e d !d o w n )!—!see!Figure!41.!!!
!
Figure&41! Cumulative$ optical$ aberrations$ place$ limits$ on$ lens$ resolution$ near$ wide$ aperture$
settings$and$diffraction$places$other$limits$as$the$lens$aperture$is$stopped$down$
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