ISO invarijantnost

master's thesis

• Author: Matej Tandara
• Mentor: Maja Strgar Kurečić (mentor)
• Committee member: Lidija Mandić (član povjerenstva)
• Committee member: Maja Strgar Kurečić (član povjerenstva)
• Committee member: Jesenka Pibernik (član povjerenstva)
• Granter: University of Zagreb; Faculty of Graphic Arts; Zagreb
• Defense date and country: 2022-9-29, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Graphic Technology

Abstract

U analognoj fotografiji je ISO vrijednost označavala fizičko svojstvo fotografskog

filma te je ovisila o veličini zrnaca srebrovog halida. Dolaskom digitalne

fotografije se uloga ISO vrijednosti u potpunosti promijenila jer više nije bila

nikakvo fizičko svojstvo digitalnog CMOS senzora već je ovisila o analognim i

digitalnim amplifikatorima unutar fotoaparata. Polako se počelo pojavljivati

pitanje o tome je li uopće bitno ako se ISO vrijednost namjesti prilikom snimanja

fotografija ili prilikom uređivanja RAW fotografija u programu za obradu slika -

odnosno, je li ISO vrijednost invarijantna?

U eksperimentalnom dijelu su uspoređene fotografije kojima je ISO vrijednost

bila namještena u fotoaparatu tako da je ekspozicija bila ispravna te fotografije

koje su uslikane s potpuno istim postavkama - osim ISO vrijednosti koja je bila

snižena tako da se dobiju postepeno podeksponirane fotografije.

RAW formati podeksponiranih fotografija su nakon toga bili uvezeni u Adobe

Lightroom gdje im je ekspozicija izjednačena s fotografijom čija je ISO

vrijednost ispočetka bila ispravno postavljena.

Rezultati eksperimenta su pokazali kako postoje rasponi unutar ISO vrijednosti

fotoaparata gdje ISO invarijantnost odlično funkcionira te najviše ovisi o backend read noise-u fotoaparata te da toliko raznih faktora utječe na istu da je

nužno poznavati arhitekturu fotoaparata, izvore šuma u digitalnoj fotografiji i

vrste amplifikacije signala kako bi se mogao iskoristiti puni potencijal ISO

invarijantnosti.

Abstract (english)

In analog photography, the ISO value indicated the physical property of the

photographic film and depended on the size of the silver halide grains. With the

rise of digital photography, the role of the ISO value changed completely

because it was no longer a physical property of the digital CMOS sensor, but

depended on analog and digital amplifiers inside the camera. Slowly, the

question began to arise as to whether it even matters if the ISO value is

adjusted when taking photos or when editing RAW photos in an image editing

program - that is, is the ISO value invariant?

In the experimental part, photos where the ISO value was set in the camera so

that the exposure was correct were compared with photos that were taken with

exactly the same settings - except for the ISO value, which was lowered so that

gradually underexposed photos were created.

The RAW formats of the underexposed photos were then imported into Adobe

Lightroom, where their exposure was equalised with the photo whose ISO value

was set correctly from the beginning.

The results of the experiment showed that there are ranges within the ISO value

of the camera where ISO invariance works great and depends mostly on the

back-end read noise of the camera and that so many different factors influence

it that it is necessary to know the architecture of the camera, sources of noise in

digital photography and types of amplification signal so that its full potential can

be used.

• Keywords: ISO invarijantnost; digitalni CMOS senzor; analogni i digitalni amplifikatori; back-end read noise
• Keywords (english): ISO invariance; digital CMOS sensor; analog and digital amplificators; back-end read noise
• Language: croatian
• URN:NBN: urn:nbn:hr:216:308512
• Study programme: Title: Graphic technology; specializations in: Graphic technology, Design of graphic products; Course: Graphic technology; Study programme type: university; Study level: graduate; Academic / professional title: sveučilišni/a magistar/magistra inženjer/inženjerka grafičke tehnologije (sveučilišni/a magistar/magistra inženjer/inženjerka grafičke tehnologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Closed access
• Created on: 2024-04-18 23:38:36