Which filter(s) for Medium Gunship Gray?

[RobertF]

Hello all,

 

I am currently building the 1/72 Hobby Boss F-15E as based at Lakenheath in the early '90s, so in the rather dull one colour scheme of Medium Gunship Gray  (FS x6118). I'd like to break up this scheme a bit, but I am not a fan of the weathering technique of lightening the centres of panels.

So I thought that, apart from giving the panel lines a light wash, I'd try my hand at applying a filter. 

 

But: which colour should I use to give this dark grey a more used look?

 

Thanks for your help!

 

Robert