把材料處理成會起反應
這一組就是核心畫面本身：紙、底片、印刷版被塗上藥劑，從此見光就變。
verb · C2
To treat a material or a piece of equipment so that it will react to light, heat or a chemical change — for example, coating paper so that a picture appears on it when light falls on it.
使感光
核心畫面
Think of a plain sheet of paper that has been treated in a darkroom. Nothing about it looks different, but now light leaves a mark on it. Sensitize is that treatment: you do something to a thing — a sheet of paper, a body, a person's attention — and afterwards it answers to what it used to let pass.
可以想成一張在暗房裡處理過的白紙。外表看不出任何差別，可是從此光一照上去，就會留下痕跡。sensitize 可以想成…更多收起
可以想成一張在暗房裡處理過的白紙。外表看不出任何差別，可是從此光一照上去，就會留下痕跡。sensitize 可以想成就是做這個處理的動作：對一樣東西動點手腳——那樣東西可能是相紙、可能是身體、也可能是一個人的注意力——處理完以後，它就會對本來會放過去的東西起反應。所以這個字的重點永遠不在那個東西本身，而在「處理前」和「處理後」的差別。From the word’s history
Wiktionary gives the word as sensitive + -ize, that is, to make something sensitive. The modern uses all keep that shape: something is made able to react.
Wiktionary 記的是 sensitive（敏感的）加上 -ize（使變成），也就是「使某樣東西變敏感」。今天的每個用法都還留著這個形狀：有人動了手，那樣東西才變成會起反應的。
Wiktionary entry for sensitize (kaikki:3f6f69a190036ae4:1355331696:13300)
Three branches
把身體調成會起反應
把被處理的東西從紙換成活的身體：同樣是處理之後才開始有反應，只是這次反應發生在皮膚、細胞或神經上。
verb · C2
To make a body, a part of the body, or living cells react more strongly to something, so that a small amount of it, or a small change, is now enough to produce a reaction. This use does not say the reaction is a bad one.
使變敏銳
把注意力調成看得見
這次被處理的是一個人的注意力。處理過後，本來從眼前走過去的事，他會停下來看一眼。
verb · C1
To help someone notice and understand a problem or a situation, usually by giving them real experience of it or clear information about it, so that they keep noticing it afterwards.
使意識到