Is there no way to control to opacity of a layer?

[Stokestack]

Hi all.

I'm doing a two-layered drawing, and I want to fade the back layer so I can use it as a guide but make it less obtrusive.

But I can't find any way to control the opacity of a layer. What gives?

Thanks!

 

[Brushman]

Lens option? nothing to do with layers you can place this over an object, put them both on the same layer and lock it. Draw on another layer, when no longer required delete background layer and both items will go. You can rename the layer to avoide confusion.
Alan D