Padiddoru

Padiddorui suratgiri, mahluli yakchand moddahoest baroi ayon sokhtani aksi noayoni fotografi. Aksi noayoni surati fotografi dar natijai ba navori kino yo lavhai fotografii hassos tasir kardani ravshani yo digar namudi afkanishot paydo meshavad.

Padiddoru du khel meshavad: muqarrari (yo khud khimiyavi) va fiziki. Padidorui kh i m i ya v i asosan mahlulest, ki chor khel moddaro darbar megirad: moddai ayonsozanda, moddai tezonanda, moddai sabt va moddai, ziddihijobi. Moddai ayonsozanda (metall, gid­rokhinon va gayra) nuqrai dar tarkibi qabati fotografi budaro barqaror mekunad. Moddai tezonanda (so­da, tezob va gayra) boisi reaksiyai ishqorii mahlul gardida, baroi tez tasir kardani moddai ayonsozanda sharoit muhayyo mekunad. Moddai sabt namemonad, ki Padidoru az tasiri oksiteni havo tez oksid shavad, inchunin tasiri khudi Padidoruro zurtar mekunad. Moddai ziddihijobi (KVg, benzotriazol) namemonad, ki dar prosessi ayonsozi dar rui aksi fo­tografi yak nav hijob, yane par­da hosil shuda, onro khira gardonad.

Fayp az Padiddorui muqarrari inchunin Padiddoruhoi makhsus ham hastand. Masalan, Padiddorui rezakholak, Padiddorui yakrangkunanda, Padiddorue, k i dar harorati baland yo past istifoda burda meshavad va gayra.

Baroi ayonsozii surathoi rangai noayoni fotografi ba Padiddorui muqarrari hosilahoi parafenilendiamin ilova mekunand.

Padiddorui f i z i k i in moddahoi ayonsozandai NajS va AgNOe meboshand. Dar ayni in prosess AgN0₃ chun khokai rezakholaki nuqra barqaror gar­dida, dar joyhoi lozimi surati fo­tografi tahshin meshavad. Zamini in guna suratho rezakholak buda, khu­di onho ravshanu vozeh meshavand.