Budewa wani muhimmin bangare ne na kyamarar zuƙowa, kuma tsarin sarrafa buɗaɗɗen zai shafi ingancin hoto. Na gaba, za mu gabatar da alaƙar da ke tsakanin buɗaɗɗen buɗaɗɗiyar da zurfin filin a cikin kyamarar zuƙowa daki-daki, don taimaka muku fahimtar menene da'irar watsawa.

1. Menene budewa?

Aperture wata na'ura ce da ake amfani da ita don sarrafa adadin hasken da ke shiga cikin ruwan tabarau.

Don ruwan tabarau da aka kera, ba za mu iya canza diamita na ruwan tabarau yadda muke so ba, amma za mu iya sarrafa hasken ruwan tabarau ta hanyar rami mai siffa mai nau'in grating tare da sassa daban-daban, wanda ake kira aperture.

Dubi a hankali ga ruwan tabarau na kyamarar ku. Idan ka duba ta cikin ruwan tabarau, za ka ga cewa budewar ta ƙunshi ruwan wukake da yawa. Za a iya janye ruwan wukake da ke kafa buɗaɗɗen buɗe ido don sarrafa kaurin hasken da ke wucewa ta cikin ruwan tabarau.

Ba shi da wahala a fahimci cewa girman buɗaɗɗen buɗaɗɗen shine, girman giciye - yanki na katako da ke shiga kyamara ta buɗewa zai kasance. Akasin haka, ƙaramin buɗaɗɗen buɗaɗɗen shine, ƙaramin giciye-yankin katako da ke shiga kyamara ta ruwan tabarau zai kasance.

2. Nau'in budewa

1) Kafaffen

Kyamara mafi sauƙi tana da kafaffen buɗaɗɗen buɗe ido tare da rami madauwari.

2) Idon Cat

Bude idon cat ɗin ya ƙunshi takardan ƙarfe mai siffar kwali ko lu'u-lu'u a tsakiya, wanda ya kasu kashi biyu. Za a iya kafa buɗaɗɗen ido na cat ta hanyar daidaita zanen ƙarfe guda biyu tare da wani rami mai siffa mai siffar murabba'i ko rabin lu'u-lu'u da motsa su dangane da juna. Ana amfani da buɗe ido na Cat sau da yawa a cikin kyamarori masu sauƙi.

3) Iris

Ya ƙunshi tarin baka masu rufin asiri - siraran ruwan wukake na ƙarfe. Maƙarar ruwan wukake na iya canza girman buɗewar madauwari ta tsakiya. Yawancin ganyen diaphragm na iris da kuma mafi girman siffar rami mai madauwari, ana iya samun mafi kyawun tasirin hoto.

3. Aperture coefficient.

Don bayyana girman buɗewa, muna amfani da lambar F azaman F/ . Misali, F1.5

F = 1/ diamita budewa.

Budewa baya daidai da lambar F, akasin haka, girman buɗaɗɗen ya yi daidai da lambar F. Misali, ruwan tabarau mai babban budewa yana da ƙaramin F lamba da ƙaramin buɗewa; Lens mai ƙaramin buɗe ido yana da babban lambar F.

4. Menene zurfin filin (DOF)?

Lokacin ɗaukar hoto, bisa ka'ida, wannan mayar da hankali zai zama mafi bayyananne matsayi a cikin hoton hoto na ƙarshe, kuma abubuwan da ke kewaye za su ƙara ɓaci yayin da nisa daga mayar da hankali ya karu. Matsakaicin bayyananniyar hoto kafin da bayan mayar da hankali shine zurfin filin.

DOF yana da alaƙa da abubuwa uku: nisa mai da hankali, tsayin hankali da buɗe ido.

Gabaɗaya magana, mafi kusancin nesa mai nisa shine, ƙaramin zurfin filin shine. Tsawon tsayin mai da hankali shine, ƙaramar kewayon DOF shine. Mafi girman buɗaɗɗen buɗaɗɗen shine, ƙaramin kewayon DOF shine.

5. Mahimman abubuwan da ke ƙayyade DOF

Budewa, tsayin hankali, nisan abu, da dalilin da yasa waɗannan abubuwan ke shafar zurfin filin hoto shine ainihin abu ɗaya: da'irar ruɗani.

A cikin na'urorin gani, lokacin da haske ya ratsa ta cikin ruwan tabarau, zai hadu a wuri mai mahimmanci don samar da madaidaicin ma'ana, wanda kuma zai zama mafi bayyananne wurin hoto.

A haƙiƙa, saboda ɓarna, hoton ma'anar abin ba zai iya haɗuwa a wuri guda kuma ya samar da tsinkayar da'irar da'irar a kan hoton hoton, wanda ake kira da'irar watsawa.

Hotunan da muke gani a zahiri sun kunshi manya da kanana da'irar rudani. Da'irar ruɗani da aka kafa ta wurin a wurin mayar da hankali shine mafi bayyana a kan hoton. Diamita na da'irar rikicewar da aka kafa ta wurin gaba da baya na mayar da hankali kan hoton a hankali yana girma har sai an gano shi da ido tsirara. Wannan da'irar rikice mai mahimmanci ana kiranta "da'irar rikicewar da aka yarda". An ƙayyade diamita na da'irar ruɗani da aka yarda ta hanyar iya gane idon ku.

Nisa tsakanin da'irar rudani da aka yarda da kuma mayar da hankali yana ƙayyade tasirin hoto, kuma yana rinjayar zurfin wurin hoto.

6. Daidaitaccen Fahimtar Tasirin Buɗaɗɗiya, Tsawon Hankali da Nisan Abu akan Zurfin Filin

1) Mafi girman budewar, ƙananan zurfin filin.

Lokacin da filin kallon hoton, ƙudurin hoto da nisan abu aka gyara.

Buɗewa na iya canza nisa tsakanin da'irar ruɗani da aka yarda da hankali ta hanyar sarrafa kusurwar da aka haɗa lokacin da hasken ya shiga cikin kyamara, don sarrafa zurfin filin hoton. Ƙananan budewa zai sa kusurwar haɗin haske ya zama ƙarami, yana barin nisa tsakanin da'irar watsawa da mayar da hankali ya zama tsayi, kuma zurfin filin ya zama zurfi; Babban buɗaɗɗen buɗewar yana sa kusurwar haɗin haske ya fi girma, yana barin da'irar ruɗani ta kasance kusa da abin da aka fi mayar da hankali da zurfin filin don zama mai zurfi.

2) Yayin da tsayin tsayin daka, zurfin filin ya ragu

Tsawon tsayin dakaru, bayan hoton ya kara girma, da'irar rudani da aka yarda za ta kasance kusa da abin da aka mayar da hankali, kuma zurfin filin zai zama mai zurfi.

3) Matsakaicin kusancin harbin shine, zurfin filin yana da zurfi

Sakamakon raguwar nisan harbi, daidai da canjin tsayin daka, yana canza girman hoton abu na ƙarshe, wanda yayi daidai da faɗaɗa da'irar rudani a cikin hoton. Matsayin da'irar ruɗani da aka yarda za a yanke hukunci don zama kusa da mayar da hankali da zurfi a cikin zurfin filin.