Owner's Manual

14.0&&&&&&SUMMARY!
The!EOS!system!is!hugely!established!across!the!globe!and!continues!to!move!in!new!directions!—!as!the!
lines! b et w e en ! still! and ! motion ! imagin g! blur! and! as! lens-camera! image! quality! steadily! increases! with!
every!generation.!!Applications!of!still!and!motion!imaging!have!seen!extraordinary!advances!at!all!levels!
—!from!amateur!all!the ! way!to!the!h igh es t! p ro fess ion als.!!Colle ctively ,! a esth etic!aspiratio n s!and!creative !
ingenuit ie s!of!the!en d !u s er s!are!escalat in g!—!and!the!bar!continues!to!be!elevated!in!requirements!for!
both!image!quality!and!operational!freedoms.!
The!recognition!that!all!that!is!best!about!the!EOS!system!must!be!supported!into!the!future!is!tempered!
by!an!acknowledgement!that!new!design!options!needed!to!be!opened.!!!!The!new!EOS!R!system!was!
spawned! by! the! vast!a ccum ulation! of! EOS! system! experiences! over! the!past! decades,! by! accelerating!
technologica l! advan ces ! in! optics,! image! senso rs! and! digital!image! processing! over!m ore! recent! years,!
and! by!a!growing!recognition!that!ongoing!enhancements!to! the!system!would!require! m ore!degrees! of!
design!freedom!for!lenses!and!cameras.!!!
A!long!examination!by!Canon!R&D!and!Lens!Development!groups!—!on!both!the!optical!and!camera!side!
—! concluded! that! optics! w as! central! to! a! new! future! strategy.! ! In! the! context! o f! the! digital! camera,!
Moore’s!Law!remains!amazingly!resilient!from!its!first!promulgation!at!the!end!of!the! 1970’s! —!there!as!
yet! seem s! no! en d! in ! sight.! ! As! a! co n se q u e nc e ,! d igit al! camera! pro ce s sin g ! h a s! b e n ef ite d ! to ! a n !
extraordinary! level! —! as! testified! by! the! huge! range! available! today,! their! continuing! performance!
elevations,!and!their!steadily!decreasing!size!and!weight.!!!!It!must!be!anticipated!this!will!continue.!!!
Lenses,! on!the! other! hand,! enjoy!no! equivalent! technological!stimulant.! ! !! The! sciences! of!optics! and!
optomechanics! advance! methodically.! Yet,! the! dictates! of! higher! optical! performance,! greater!
flexibilities!in!op era tion al!specific a tio n s,!and !the !intrac ta b le!con s tra in ts!of!size!and !we igh t !of!lenses !are!
pivotal!to!supporting! future! prospects!in! imaging.! ! EOS! R! system! was! born!on!the! basis! of! decisively!
removing!so m e !con strain ts!on !lens!d esign s.!
Central!to!the!new!EOS!R! system!strategy!was!the! recognition!that!the! large!54! m m! diameter! of!the! EO S!
system! w o uld!continue!to!pay!optical! d ividends!far!into! th e!future.!! Bu t!the!44!mm!flange!back!distance!
had! surfaced! as! a! constraint! whose! time! had! come! to! be! dealt! with.! ! Significantly! shortening! this!
distance!would! yield!immediate! new!degrees! of!freedom! in!optical!design.! !But!this,!of!necessity,!would!
have!to!be!balanced!with!rigidity!of!the!new!mount,!ease!of!attaching!and!detaching!lenses,!durability,!
dust! and! drip! resistance.! ! ! In-depth! design! reviews! within! Canon! yielded! the! new! RF! lens! mount! —!
preserving!the!54! mm! inner! diameter!while! significantly!shortening!the! flange!back!to!20! mm.!! Now,!
positioning!of!large!diameter!lens!elements!much!closer!to!the!image!sensor!(especially!the!full!fram e !
sensor)!would!support!an!imp ortant!enh ancem en t!of!image!quality.!
This!p aper!has!discussed!details!of!the!new!RF!lens!mount.!!!The!advantag e s!of!this!new!m o u n t!design!
are! immed iately! evident!in!the!designs! of!the!first!fo u r!len ses !o f!the !RF!lens!fam ily!—!as!outlined!in!this!
paper.!
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