Choros is a film of a single dancer (Terah Maher) who performs on a simple stage by herself. So far it doesn't sound too engaging and I guess if it were screened just as it was filmed then perhaps it would not have been. However in this case the post-production is where the film very much comes alive as the film of Maher dancing has essentially been duplicated and run 10 or so times with a slight time gap between each. This leads to the visual effect of a trail of one person's movement with ghost images making up that trail, although at other times the images are also physically offset so that Maher appears to be an entire troupe of dancers performing together in perfect coordination.
I say "essentially been duplicated" to describe it, but I have no idea how this was done but can only imagine it took a lot of time and skill since the images move very well and in good timing to one another and to the music. The end result is quite hypnotic. You do tend to lose the detail of the dance moves in some cases, which is a downside; so for example movements all done in one spot soon lose the individual into a blur of the movements. However it must be said that this blur is also visually interesting and beautiful. At 13 minutes I did wonder if it was too long for this one idea but, while it could have lost a few minutes, the gradual build in scale and location as well as the idea of death and then triumphant rebirth just about make the time work.
It is technically very impressive but it still also works as a piece of performance and the digital work may change that, but only in a way that transforms and adds.