Phunzirani Zambiri Zambiri za Dynamic Range ndi Tonal Range mu Digital Photography
Ngati munayamba mwadzifunsapo kuti njira zamakono ndi tonal zimakhudza bwanji zotsatira zanu zojambula zithunzi, simuli nokha. Zithunzi ziwirizi zingakhale zosokoneza poyamba, koma mukhoza kusintha zithunzi zanu za DSLR mwa kuphunzira momwe amagwirira ntchito.
Kodi Mphamvu Yotani?
Makamera onse a DSLR ali ndi chithunzithunzi chojambula chithunzichi. Makina amphamvu kwambiri a sensor amatanthauzidwa ndi chizindikiro chachikulu chotheka chomwe chingapange chogawanika ndi chizindikiro chochepa kwambiri chotheka.
Chizindikiro chimapangidwa pamene ma pixel a chithunzi cha kamera amajambula photons, zomwe zimasanduka magetsi.
Izi zikutanthauza kuti makamera omwe ali ndi mphamvu zazikuluzikulu amatha kulumikiza zonse ziwiri ndizithunzi zamthunzi panthawi imodzi komanso mwatsatanetsatane. Mwa kuwombera mu RAW , mphamvu yaikulu ya sensa imasungidwa, pamene JPEGs ingasinthe mfundo chifukwa cha kuponderezedwa kwa mafayilo ogwiritsidwa ntchito.
Monga tanenera kale, ma pixel pa sensa amatha kusonkhanitsa photons pamene akuwonetsedwa ndi fano. Kuwala kumakhala kosavuta, pomwe zithunzi zambiri zimasonkhanitsidwa. Pachifukwa ichi, ma pixel akusonkhanitsa mbali zowala za fano amasonkhanitsa mafoto awo onse mofulumira kuposa ma pixel omwe akusonkhanitsa mbali zakuda. Izi zingapangitse kusefukira kwa photons, zomwe zingayambitse kufalikira .
Zovuta ndizitali zambiri zingathe kuwonetsedwa muzithunzi zosiyana. Ngati kuwala kumakhala koopsa kwambiri, kamera ikhoza 'kuwomba' zomwe zimawoneka bwino ndipo sizisiya tsatanetsatane m'madera oyera a fano. Ngakhale diso la munthu lingathe kusintha chifukwa cha zosiyana siyana ndi zindikirani, kamera sangathe. Izi zikachitika, tikhoza kusinthiratu chiwonetserochi posiya kapena kuwonjezera zowonjezera kuwala kuti tipewe kusiyana komwe kumagwera pa phunzirolo.
DSLRs ali ndi kukula kwakukulu kuposa mfundo ndi kuwombera makamera chifukwa masensa awo ali ndi pixelisi zazikulu. Izi zikutanthauza kuti ma pixel ali ndi nthawi yokwanira yosonkhanitsa photons mbali zonse zowala ndi zakuda za fano popanda kusefukira.
Kodi Tonal Range ndi chiyani?
Mtundu wa tonal wa chithunzi cha digito umakhudzana ndi chiwerengero cha mawonedwe akuyenera kufotokozera kukula kwake.
Mizere iwiriyi ikugwirizana. Kukula kwakukulu kwakukulu kuphatikizapo Analog to Digital Converter (ADC) ya mabomba 10 osakanikirana molingana ndi kukula kwa tonal. (ADC ndi gawo la kusintha ma pixelisi pa chithunzi cha digito mu chithunzi chowoneka.) Mofananamo, ngati chojambulira ndi ADC cha makilogalamu 10 chikhoza kutulutsa zizindikiro zambiri, zidzakhala ndi kukula kwakukulu.
Chifukwa masomphenya aumunthu ndi osakhala ofanana, mwina onse awiri omwe ali ndi mphamvu komanso ophwanyika amayenera kupanikizidwa ndi mpikisano wa tonal kuti ukhale wosangalatsa kwambiri. Zoonadi, mapulogalamu a kusintha kwa RAW kapena kukamera kwa kamera amatha kugwiritsa ntchito mpikisano yofanana ndi S kuti ikhale ndi deta kuti athetseketsa njira yayikulu yowonetsera kapena yosamala.