ISO Kya Hai โ Basics
ISO teen exposure controls mein se ek hai (dusre do: aperture aur shutter speed). Yeh sensor ke signal ko electronically amplify karta hai jab light kam ho. Lekin yeh ek trade-off ke saath aata hai โ jitna zyada aap amplify karte ho, utna zyada noise (grain/speckling) bhi introduce hota hai image mein.
Isiliye ISO ko "free brightness boost" samajhna galat hai โ yeh dark scene ko bright toh kar deta hai, lekin quality cost pe.
Native ISO Kya Hota Hai
Har sensor ka ek "native" ya "base" ISO hota hai โ woh specific value jahan sensor bina kisi additional amplification ke apni sabse clean, sabse zyada dynamic range wali image capture karta hai. Zyaadatar cameras mein yeh ISO 100 ya ISO 200 hota hai (log profiles mein aksar higher, jaise 400 ya 800, kyunki flat curve zyada base sensitivity maangta hai).
Native ISO se upar ya neeche jaate hi, camera ya toh electronically amplify karta hai (upar) ya signal ko artificially reduce karta hai (neeche) โ dono cases mein image quality thodi compromise hoti hai compared to native point.
Dual Native ISO Kya Hai
Kuch advanced sensors (jaise Blackmagic Pocket Cinema Cameras, Panasonic S5 series, aur kuch cinema cameras) mein ek unique design hota hai jisme do alag "native" clean points hote hain โ ek low-light ke liye (jaise ISO 800), ek bright light ke liye (jaise ISO 100). Sensor circuitry is tarah design ki jaati hai ki dono points pe minimal noise ho, jabki beech ke ISO values mein interpolation hoti hai.
Visual Comparison
ISO Aur Grading Ka Connection
Native ISO pe shoot kiya gaya footage grading mein sabse zyada flexibility deta hai kyunki uska dynamic range full potential pe hota hai. Jab aap native ISO se bahut door jaate ho (bahut high ya bahut low), dynamic range compress hoti hai, aur shadows push karne pe noise/banding jaldi expose ho jaata hai.
Practical Tips ISO Ke Liye
1. Apne Camera Ka Native ISO Pata Karo
Log profile mein shoot karte waqt manual ISO ka base value manufacturer ki documentation mein check karo โ zyaadatar yeh camera ke standard base se different hota hai.
2. Native ISO Ke Multiples Pe Shoot Karo
Agar dual native ISO camera hai, uske dono native points (jaise 400 aur 3200) ke close values use karna cleanest result deta hai, beech ke arbitrary values avoid karo jab possible ho.
3. Zyada ISO Se Darna Nahi Chahiye โ Agar Woh Native Hai
Dual native ISO sensor pe high native ISO use karna low native ISO jitna hi clean hoga โ bas correctly expose karna zaroori hai.
Quick FAQ
Q: Native ISO aur base ISO mein kya farak hai?
Zyaadatar practical use mein yeh same cheez consider ki jaati hai โ sensor ka cleanest, no-amplification-needed sensitivity point.
Q: Kya dual native ISO wali camera hamesha better hoti hai?
Low-light flexibility ke liye haan, lekin overall image quality bhi sensor size aur processing pe depend karti hai, sirf dual native ISO pe nahi.
Q: Kya high ISO hamesha noisy image deta hai?
Agar woh camera ka native/dual-native point nahi hai toh haan, noise badhta hai. Lekin agar woh ek native point hai, noise minimal reh sakta hai.
Q: ISO badhane se dynamic range pe kya asar padta hai?
Generally native ISO se door jaane pe dynamic range thodi compress hoti hai โ shadows aur highlights dono mein detail recovery kam ho jaati hai.
ISO ka technical side clear ho gaya? Ab footage ko grade karke professional look dena seekho.
Check out Decoding DaVinci Resolve โ