Dumb question but does the lensing distort what we would see if there was no lensing at all? Or does that information get compressed as part of the lensing and we need to "stretch" it out to see it?
Anyway, the test of GR in the actual article does not appear to use or reference lensing at all. It's about looking at the orbit of a star in an extreme gravitational environment and comparing it to what Newtonian models would predict.
> The team compared the position and velocity measurements from GRAVITY and SINFONI respectively, along with previous observations of S2 using other instruments, with the predictions of Newtonian gravity, general relativity and other theories of gravity. The new results are inconsistent with Newtonian predictions and in excellent agreement with the predictions of general relativity.
The conservation of information means that the phase space of a system is incompressable. I believe this is equivalent to saying we can just stretch the image out, within the limits of our ability to resolve detail.
