Correct Camber setting?

[Urbalizer]

My front wheels currently have a 1 deg negative camber, a test driver took my car for a spin and said it needed more of a negative camber.
What is the correct negative camber setting?
I also have signs of wear on the outer tread, but the inner tread looks almost untouched, is this down to the same thing?

[mrdemon]

Was told you cannot ajust camber which i find shocking, looks like we will have to machine what is needed.

[daddysumo]

The amount of camber you run is linked to how stiff your car is and how you drive it and where.Road settings are not ideal for track and vise versa so a compromise is usual unless you want to be swapping shims out regularly or wearing tyres out unevenly.
You also run 10 degs pos castor (alot for a standard road car)which adds dynamic neg camber when cornering.
The more tech heads on here can advise better than me but I set mine at 1.5 degs neg.
The wear could also be toe related.