Txawm tias ntau qhov ntawm cov koob yees duab digital tseem ceeb, lub lens yuav yog qhov tseem ceeb. Tsis muaj lub lens zoo, koj cov duab tsis muaj caij nyoog rau qhov ntse thiab kaj. Txawm li cas los nws yuav nyuaj rau decipher qhov txawv sib txawv ntawm lo ntsiab muag uas tsis paub txog qee cov koob yees duab terminologies rau cov lo ntsiab muag. Nws yuav ua tau me ntsis ruam rau kom nkag siab qee cov ntsiab lus uas siv nrog lo ntsiab muag.
Thaum mus yuav khoom rau lub koob yees duab, xyuas kom koj xaiv hom lens uas yuav ua haujlwm zoo rau koj qhov teeb meem los ntawm kev kawm cov koob yees duab tseem ceeb tshaj plaws ntawm cov lens.
- Zoom. Qee cov duab yog hais txog zoom li cov duab ntawm tus duab, uas cia tus kws yees duab tua cov duab "close-up" tsis tau txav mus ze rau qhov kev kawm. Txawm li cas los, qhov tseeb txhais rau zoom yog lub peev xwm ntawm lub lens mus tua ntawm ntau lub focal ntev. Hauv lwm lo lus, lub lens zoom yuav tua cov kab mob dav dav los yog txhaj tshuaj tiv thaiv kab mob los yog ob qho tib si. Tsis yog txhua qhov lo ntsiab muag muaj peev xwm ua kom nruj heev.
- Optical zoom. Optical zoom yog lub peev xwm los hloov lub focal ntev ntawm lub lens siv kho vajtse hauv lub lens hloov lub focal ntev. Optical zoom yog txoj kev nyiam dua ntawm zoom, raws li nws tsis cuam tshuam rau cov duab sharpness vim kev tso siab ntawm qhov kho vajtse hauv lub lens kom hloov. Optical zoom yog ib qho muaj nyob nrog cov lens tsau, uas tsis yog DSLRs.
- Cov duab zoom. Digital zoom yog hom zoom qhov twg software hauv lub koob yees duab hloov lub focal ntev los ntawm kev ua kom nrov loj tuaj. Vim hais tias digital zoom yuav nce qhov loj ntawm pixels, digital zoom tej zaum yuav cuam tshuam rau cov duab sharpness. Thaum muas lub koob yees duab, tsis txhob tsom rau digital zoom, vim feem ntau cov kev sib tw yuav thim tau ntau yam ntawm digital zoom nrog kev tsim tawm software. Tshem xim rau cov zauv ntawm qhov muag xwb.
- Cov lenses sib txawv. High-end, DSLR koob yees duab, thiab daim iav tsis muaj lub koob yees duab yuav ua rau siv cov lenses sib pauv, qhov lens nyias txawv nyias. Muaj ntau yam sib txuas ntawm DSLR thiab lauj laub tsis muaj mirrorless, duab stabilization ua rau lub lens, limiting koob yees duab co thiab txhim kho cov duab zoo.
- Focal ntev. Lub focal ntev yog ntsuas ntawm qhov kev ncua deb ntawm qhov chaw ntawm lub lens mus rau focal point (uas yog cov duab sensor hauv lub koob yees duab digital). Feem ntau cov koob yees duab lens nthuav qhia cov lens 'kev ntsuas hauv kev ntsuas qhov ntev, xws li 25mm-125mm. Qhov kev ntsuas hauv focal ntev yog ntau qhov ntsuas lub telephoto thiab wide-angle ntawm lub lens tshaj qhov ntsuas qhov muag optical, uas tsuas yog ib tug zauv cim qhia qhov txawv ntawm qhov dav dav thiab telephoto ntsuas. Nyob rau saum toj no 25 hli-125 hli, nws yuav muaj 5X optical zoom ntsuas.
- LCD. Cov kua siv lead ua kua (LCD) nyob tom qab ntawm lub koob yees duab digital yuav siv los thaij duab, zoo li lub qhov yeeb yam. Txawm li cas los xij, nco ntsoov tias tus LCD tsis tshua muaj 100% ntawm daim duab uas lub koob yees duab yuav tua. LCD cov kev pab qee zaum kuj yog 95% lossis siab tshaj, thiab feem pua qee zaus teev nyob rau hauv lub koob yees duab cov lus qhia. Nws feem ntau zoo sib xws ntawm lub lens, tab sis nws tsis raws nraim nws.
- Optical viewfinder. Qhov pom kev kho qhov muag pom kev muab kev pabcuam tsis-muaj zog, tsis saib cov duab ntawm tus duab kws yees duab los tua. Cov low-end, taw tes thiab tua cov koob yees duab, qhov kev kho qhov muag pom tsis tau khi rau lub lens optics - txhais tau tias, nws yog feem ntau ntawm lub lens - lub ntsiab lus nws yuav tsis precisely match cov duab lub lens yuav tua. High-end, DSLR koob yees duab khi qhov kho qhov muag viewfinder rau lens optics, muab kev saib zoo meej ntawm cov duab tom ntej.
- Hluav taws xob hauv hluav taws xob (EVF). Lub EVF nyob rau hauv ib lub digital koob yees duab yog ib tug me me LCD uas muab tus kws yees duab lub caij nyoog rau tha duab. Lub EVF yog cov sawv cev ntawm cov duab. Nyob rau hauv cov nqe lus ntawm mimicking qhov saib los ntawm lub lens ntawm zaum kawg yees duab, EVF zoo sib xws rau LCD's raug.