Aperture vs F-Stop
Aperture thiab F-Stop yog ob qho tseem ceeb hauv kev yees duab. Hauv optics, thiab cov tub ntxhais kawm ntawm kev yees duab yuav txaus siab rau qhov no, f-number, tseem hu ua f-stop, hais txog lub cheeb ntawm cov tub ntxhais kawm nkag mus rau qhov focal ntev ntawm lub lens ntawm lub koob yees duab. Rau ib tug layman, f-stop yog qhov piv ntawm focal ntev thiab txoj kab uas hla ntawm lub lens. Nws muaj qhov tseem ceeb hauv kev yees duab, thiab feem ntau yog tus lej uas qhia txog lub lens ceev.
Cia peb xub saib seb Aperture yog dab tsi. Nws yog qhov loj ntawm qhov qhib hauv lub lens thaum thaij duab. Thaum ib tug ntaus lub shutter, ib lub qhov opens uas tswj tus nqi ntawm lub teeb mus rau hauv. Lub teeb no tso cai rau lub sensor hauv lub koob yees duab los ntes qhov pom ntawm qhov chaw uas tus neeg siv xav ntes. Aperture feem ntau ntsuas hauv f-stops. Yog li, hais ncaj ncees, f-stop qhia peb tias qhov qhib hauv lub lens loj npaum li cas thaum daim duab raug coj mus.
Loj f-stops txhais tau hais tias lub lens muaj qhov qhib me dua, thaum me me f-stops txhais tau tias qhov qhib loj. Feem ntau f-ntaus yog f/2 txog f/22. f/22 txhais tau hais tias me me heev, yuav luag cov kab plaub hau qhib, qhov f/2 qhia txog lub qhov loj. Lens ib txwm qhib dav; Nws tsuas yog thaum lub shutter nias lub lens hniav tawm thiab npog lub lens ua kom nws qhib me me raws li qhov koj xav tau.
Cov kws yees duab nyiam tham txog apertures thiab f-stops yuav luag sib hloov. Qhov tsuas yog qhov uas yuav tsum nco ntsoov yog tias ob qho tib si sib cuam tshuam yog li f-stop nce mus, qhov aperture loj poob qis thiab vice-versa.
Txo f-stop muaj peb qhov teebmeem:
• Nws tso cai rau lub teeb nkag mus rau hauv ntau, yog li ua rau kom raug
• Txo qhov tob ntawm thaj teb, ua rau tom qab ntau qhov muag plooj
• Zuag qhia tag nrho ntawm cov duab txo qis
Summary
• f-stops thiab aperture yog cov ntsiab lus siv hauv kev yees duab
• Aperture yog qhov loj ntawm qhov qhib ntawm lub lens uas tso cai rau lub teeb nkag mus rau hauv, thaum f-stops yog qhov sib piv ntawm focal length thiab txoj kab uas hla ntawm lub lens
• Aperture yog inversely proportional rau f-stop
