Below are my cartouche and ghost sign. I used a process of painting with casein on plastic and then transferring the image onto my ground using acrylic flat as my adhesive. Once dry, I'd peel the plastic off like a band-aid and only parts of what I transferred would actually stick to the surface, thus giving it a "ghosted" look.
My lighthouse translucency using different colored gels in front and back.
A window in perspective using drop-point off of a groundplan, section, and specific observation point.