The past (1/3): 'Did Messi score?' vs. 'Has Messi scored'?
The simple past ("Did you see this") refers about an event in the past
The present perfect ("Have you seen this") suggests a link with the present time.
If "this" is something you could have seen but cannot anymore now (you should have been there seeing "this" at the time, but it wouldn't have the same impact if you see it again now), then "Did you see" is more appropriate. It is about an event that happened once in the past.
If "this" is something you can check it out whenever you want, "Have you seen" is more to the point, because it suggests that, if you haven't seen it in the past, you could consider seeing it now or in the near future. It is about an event which can happen again or is still relevant in the present.