Change the opacity of shadows in 2D

[jsanders]

Hello,

I would like to know if it's possible to change the opacity of the shadows in a simple elevation view ? Here they are too "dark" for my taste, I would like them to be less gray basically. link : http://i.imgur.com/zQ6HrdI.png

I've searched on internet and can't find anything. Is there no option at all to change the "intensity" of shadows in 2D view ? 

Thank you for your answers.

[constantin.stroescu · Accepted solution]

from Graphic Display Options > Lighting (and Shadows)

[jsanders]

Thank you.