Ntau tus kws yees duab xav tau kev txhaj tshuaj tsaus. Raws li txoj cai, cov teeb meem no yog ib txwm muaj rau cov tswv ntawm SLR koob yees duab, hauv qhov ntau ntawm kev tuav phau ntawv yog qhov dav heev. Txhawm rau tiv thaiv koj cov duab los ntawm kev tsaus ntuj, koj yuav tsum tsim kho koj lub koob yees duab ua ntej kev tua.
Ua ntej, koj yuav tsum tau xam dab tsi raws nraim lub luag haujlwm rau qhov ci ntsa iab ntawm cov duab tshwm sim. Cov txheej txheem tseem ceeb rau qhov ci ntawm kev thaij duab yog lub teeb, lossis theej, tus nqi ntawm lub teeb tsoo lub koob yees duab lub matrix (lossis zaj duab xis) thaum lub sijhawm tua. Lub teeb tau tswj hwm los ntawm ob qhov tseem ceeb: lub aperture tus naj npawb thiab qhov ntsuas kaw. Aperture yog cov khoom siv uas teeb tsa thiab hloov pauv ntau npaum li cas ntawm lub teeb nkag mus rau lub koob yees duab. Shutter ceev yog lub sijhawm thaum lub sij hawm kaw lub koob yees duab kom qhib kev nkag tau mus rau lub teeb. Ntawd yog, yog hais tias lub aperture dauv lub teeb los ntawm ntau, qhov ntsuas kaw yog los ntawm lub sijhawm. Qhov qhov dav ntawm lub qhov qhib tau qhib thiab qhov ntev tshaj ntawm lub tshuab kaw hluav taws xob ntev dua, lub ci ntsa iab cov duab yuav tig tawm, thiab hloov dua tshiab. Cov kev thaij duab novice, thaum tua thaum tsaus ntuj lossis nyob sab hauv tsev, feem ntau tsis raug teeb tsa qhov ntsuas ntawm aperture thiab shutter ceev, uas ua rau cov duab tsaus heev. Ib puag ncig tsaus ntuj ib puag ncig, qhov ntau ntawm aperture yuav tsum tau qhib (rau qhov qhib aperture, tus xov tooj yog los ntawm F 1.1. Kom F 5.6). Yog hais tias txawm lub qhov dav dav tsis pom lub teeb txaus, koj yuav tsum nce lub sij hawm raug (ntsuas ntsuas hauv vib nas this thiab feem ntawm ib pliag), tab sis nco ntsoov tias qhov ntev kaw ntev dua, ntau qhov muag plooj duab tuaj yeem yog. Kev thaij duab ntev ntev yog ua tau zoo tshaj plaws nrog rau ib qho chaw kos lossis siv qhov chaw zoo li qub kom tsis txhob ua qhov muag plooj duab. Yog yuav muaj qhov xwm txheej thaum lub kos duab lossis qhov tsim nyog nto tsis nyob ntawm tes, thiab tua cov khoom siv ntawm qhov siab tshaj plaws tau tsim tawm cov yees duab uas tsaus heev. Hauv qhov no, koj tuaj yeem hloov pauv qhov kev nkag siab - ISO. Qhov siab dua ntawm qhov kev ceev ntawm ISO, lub teeb ci duab yuav yog, tab sis xws li daim duab tuaj yeem "lis" - plam meej vim qhov dhau ntawm cov yees duab lub suab nrov vim muaj kev cuam tshuam.
