Fast FOV change and performance

Okay, so I just found some performance issue when changing the FOV.

I am using an FInterp to go from something like FOV10 to FOV90 (sniper scope) in a matter of half a second. There is quite hefty FPS drop. Goes from about 90 (zoomed in) to under 10 (during zoom-out) to about 60-70 (zoomed out).

Anyone has had this problem before? Or a solution for it? I suppose it has something to do with culled objects becoming visible again but I am not quite sure. Any input appreciated.

Answerhub post:

Look the stats how many drawcalls and triangles you are drawing with each FOV settings. Larger field of view is usually quite big performance hog.