"The picture was made of dots."
Translation:La bildo estis farita el punktoj.
I would have thought that "estis farita" meant "had been made" - pluperfect tense rather than straightforward past tense.
I think you are right in principle, but people are not always the most consistent about these more compound tenses in Esperanto, and have a tendency to use the past tense on both the verb "esti" and the participle when they use a participle related somehow to the past at all.
I wouldn't use it but I'm not entirely sure why... I think fariĝis would imply it somehow made itself.
-ig- = made
-iĝ- = become The mnemonic I like is "You make a pig become sausiĝ.
Fariĝis implies that the picture may have been something else, but then became made of dots; possibly by it's own efforts.