Take a picture, it lasts longer

[Paulus Pastor Rufus]

Suggested translation, incorporating a suggestion from Matthaeus: Me cum pinxeris, permanebit imago. (The Romans had no cameras!)

 

[Matthaeus]

let's use the two future constructs (fut II in the cum clause, fut I (regular ind.) in the main one.
me cum pinxeris, permanebit imago

 

[Paulus Pastor Rufus]

Gratias tibi ago, Matthaeus. Arbitrium tuum bonum et rectum est.