OK, using bagginsbill's tricky glass and Stefan's metal, this renders in Superfly without that blackout, if you use appropriate render settings and have a skydome/environment for the reflections to "see". The glass has thickness, i.e., it has both an outside surface and an inside surface.

I have uploaded it to the freestuff; pending approval.

I haven't tried illuminating the glass by applying strong emission to the filament; I suspect that the 1000x ambient/emission strength required would cause severe graininess. But I'll probably experiment as time permits.

In a real light bulb, the glass scatters/diffuses light from the filament, so the glass itself glows. That is how I set up the "ON" light bulb.

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

Silo Pro 2.5.6 64bit, Vue Infinite 2014.7, Genetica 4.0 Studio, UV Mapper Pro, UV Layout Pro, PhotoImpact X3, GIF Animator 5