1 6 ▁and ▁ 3 2 ▁seconds , ▁thus ▁pres erving ▁the ▁dou bling ▁sequence ), ▁plus ▁bul b . ▁ ▁The ▁X - sync ▁was ▁ 1 / 1 2 5 th ▁of ▁a ▁second . ▁ ▁The ▁camera ▁included ▁setting ▁for ▁film ▁spe eds ▁of ▁ 1 2 ▁AS A ▁to ▁ 3 2 0 0 ▁AS A . ▁ ▁The ▁EF ▁also ▁featured ▁a ▁self - timer ▁and ▁a ▁stop - down ▁meter ing ▁mode ▁which ▁could ▁also ▁be ▁used ▁for ▁depth - of - field ▁preview . ▁Sto pped ▁down ▁meter ing ▁must ▁be ▁used ▁with ▁older ▁Can on ▁F L ▁l enses . ▁The ▁mirror ▁can ▁also ▁be ▁locked ▁up ▁for ▁long ▁expos ures , ▁to ▁minim ise ▁camera ▁sh ake . ▁ ▁References ▁▁▁ ▁Can on , ▁Inc . ▁Can on ▁EF . ▁ ▁Part ▁of ▁Can on ' s ▁online ▁Camera ▁Museum . ▁ ▁F Z ▁EF ▁camera ▁Category : Products ▁introduced ▁in ▁ 1 9 7 3 <0x0A> </s> ▁D ating ▁game ▁shows ▁are ▁television ▁game ▁shows ▁that ▁incorpor ate ▁a ▁d ating ▁system ▁in ▁the ▁form ▁of ▁a ▁game ▁with ▁clear ▁rules . ▁Human ▁match making ▁is ▁involved ▁only ▁in ▁selecting ▁the ▁game ' s ▁contest ants , ▁who ▁are ▁usually ▁selected ▁more ▁for ▁the ▁am usement ▁value ▁than ▁any ▁concern ▁for ▁their ▁happiness ▁or ▁compatibility . ▁The ▁audience ▁sees ▁only ▁the ▁game ; ▁an ▁important ▁feature ▁of ▁all ▁d ating ▁game ▁shows ▁is ▁that ▁the ▁contest ants ▁have ▁little ▁or ▁no ▁previous ▁knowledge