I have a large vaulted ceiling in my house that has tongue and groove wood that has been stained fairly dark.  I would like to keep a wood look, but just lighten it a bit.  The wood does not appear to have any polyurethane or varnish on it – just stain.

I do not want to sand the boards as that will be very labor intensive and I may as well replace them if I have to do that.

Is there anything out there, like a semi-transparent stain that can go over this?  Has anyone had any success doing something like this?  Thanks.