Translation:We used a computer to reproduce that image.
that could work too, but in this case, "reproduksi" would sound too fancy to fit in with the sentence
whilst "memperbanyak" is a less fancy, more common word, which translates to copy/multiply
and copy/multiply are synonyms of reproduce
that's it i'm guessing?
haha i hope you could understand, i tried my best to explain this, CMIIW