Glass problem - incorrect refracting

Hi!
As U see at image I have incorrect refraction on the Car glass material.
Some like loupe effect. How to solve this problem? Glass is the separate mesh.
Thanks

http://img146.imageshack.us/img146/6884/glassproblemmagnifyingko4.jpg

How thick is the model of your glass? That might make problems.

And make sure it has a depth.

an IOR of 1.5 is way too much for car window glass. Bring that down to around 1.1 or 1.08 and we might have a solution.

A IOR of 1.5 is not to much. Most glass materials have a IOR around 1.5, but windows are so thin so the refraction is barley noticeable (many times it’s not worth using a refractive material for windows because it doesn’t make a difference only longer render times). The problem is probably related to the thickness as Julianh mentioned.