I know this is kind of a newby question, but is the lighting/color saturation/depth effect on the Top Gear TV show segments made by filters on the camera or effects placed later in editing?

 

Probably a combo of both.

I can't be sure but it looks like they are using graduated neutral density filters to dark the skies and ground. The shallow depth of field on some of the shots are from the camera/lens set up. The rest is probably post production.

 

I've been noticing the great cinematography in that show as well. Seems like they like to play with their equipment and try out new things. Sometimes the circle fade to black effect goes too far though.

This show could make a lot of money in prime time if there was an identical US version (with US guest stars).

 

They use filters on the camera itself for most of the Dark to light fades.
http://youtube.com/watch?v=oQM1NUmK3qA

1:10 onwards

 

Nice catch!