Performance Question

My display group hierarchy is essentially

Zoom Group -> Camera Group -> Map Group that contains everything else  (except ui stuff that doesn’t get moved or scaled)

When I say zoom, I mean adjusting xScale and yScale on Zoom Group

I am not doing any sort of culling when I zoom/pan

There are alot of non-physics images (tiled background) and a half dozen or so physics bodies in the Map Group

With physics paused (but everything created and added) I can zoom in and out and get 30fps

With physics un-paused I get 30fps zoomed in but 5 zoomed out 

Any idea why the significant drop of when zoomed out and physics is on? The number of physics elements doesn’t change (I assume the engine works on them if they are on screen or not). And, I don’t think it is a problem with showing all the static tiles since fps don’t drop when showing everything with physics off.

Thanks in advance