Qhov zoo ntawm cov duab lossis duab yeeb yaj kiab yog nyob ntawm kev ua haujlwm ntawm kev tsom xam rau ib qho yees duab lossis yees duab lub koob yees duab. Nrog autofocus, nws yog qhov tseem ceeb heev uas yuav tsum paub qhov ua haujlwm kom lub kaw lus ua kom lub koob yees duab ceev tau cov kws yees duab xav tau.
Tsim nyog
SLR lossis lub koob yees duab amateur
Cov Lus Qhia
Kauj ruam 1
Autofocus (luv luv rau AF) yog lub koob yees duab system uas tso cai rau lub koob yees duab tsom rau ib qho kev kawm uas tus kws yees duab xav kom nthuav tawm. Tsis zoo li phau ntawv tsom, thaum ib tus neeg yuav tsum tau tig lub lens lub log ntawm lawv tus kheej, AF ua haujlwm tsis muaj kev koom tes ntawm tus kws yees duab. Qee zaum, vim qhov no, qhov tawm tsam blunders tshwm sim, qhov kev xav ntawm cov muaj pes tsawg leeg hloov mus rau lwm yam kev kawm theem pib lossis ploj mus rau tom qab.
Kauj ruam 2
Autofocus tuaj yeem ua haujlwm nyob rau ob hom sib txawv: ib qho thiab txuas ntxiv. Ib qho tib qho (lossis ib qho kev txhaj tshuaj) kev ua kom pom tseeb yog qhov zoo rau kev ntes cov chaw kawm nyob ruaj ruaj (xws li xwm lossis nroog). Txhawm rau tua rau hauv cov kab lus ib leeg AF, koj yuav tsum nias lub khawm kaw ib nrab, pom lub tsom qhov xwm yeem thiab tom qab ntawd muab cov yam xav kawm hauv nws. Nruam (lossis Taug Qab) AF yog siv rau kev tua cov ncauj lus nrawm, nrog rau tib neeg, kev sib tw ncaws pob, thiab tsiaj. Txhawm rau ua haujlwm nrog autofocus txuas nrog tib txoj kev, koj yuav tsum nias lub khawm khawm ib nrab thiab tom qab ntawd pib tua.
Kauj ruam 3
Lub nrawm ntawm lub zog autofocus nyob ntawm ntau yam. Qhov tseem ceeb tshaj plaws ntawm cov no yog lub teeb pom kev zoo. Qhov tsawg dua cov teeb pom kev, qhov phem dua lub koob yees duab tsom (qhov no kuj siv rau SLR thiab cov koob yees duab kev nyiam ua haujlwm). Qhov ntau lub teeb muaj, qhov nrawm dua thiab raug qhov koob yees duab tsom. Yog li, tsis siv neeg kev tsom teeb pom kev zoo thaum tsaus ntuj thiab thaum tsaus ntuj, lossis hauv chav tsev uas tsis muaj teeb pom kev zoo ntawm lub teeb.
Kauj ruam 4
Qhov thib ob tseem ceeb rau SLR koob yees duab yog lub lens aperture. Lub teeb pom ntau dua rau AF sensors, qhov zoo dua thiab yooj yim dua lub lens yuav tsom rau txhua yam kev kawm. Lub apertures zoo yog 1, 4 thiab 1, 8. Qhov tob tob ntawm daim teb ntawm lo ntsiab muag ceev kuj tseem txhim kho AF qhov raug.
Kauj ruam 5
Qhov thib peb yam uas cuam tshuam rau kev tsom qhov tseeb yog qhov ntev ntawm koj lub lens. Qhov tsis zoo tshaj plaws tau ua tiav nrog zooms thiab superzoom (nrog qhov sib nrug mus txog 400 hli). Qhov zoo tshaj plaws, lub koob yees duab tsom rau qhov muag teeb tob tob (lawv muaj qhov feem pua ntawm qhov yuam kev tsawg).
Kauj Ruam 6
Autofocus ntawm SLR thiab ntawm cov amateur digital koob yees duab ua haujlwm zoo ib yam nkaus, yog li txhua yam hais tias yog qhov tseeb rau ib qho "xab npum tais" (tsis hais hom ntawm lub koob yees duab thiab nws cov nqi). Qhov teeb pom kev zoo dua thiab luv dua ntawm qhov focal ntev, ua kom pom tseeb thiab ua tiav koj cov kev txhaj tshuaj yuav ua tiav.
