[Aunty Betty]

Thanks moloraram and Brian.
My Giddy Aunt caustics is steep on the ol' rendering.

In some place I found that the light creep from the caustics particularly at the base of the object seemed too spectral / glowy - more so than looked natural.

The main thing is that my basic quality has improved to a point where I feel it'll be good enough for jazz. With the piece I have in mind the glass will be a minor detail yet one where a degree of believability is vital. After much comparison of quality verses time etc I think I'm now happy to proceed.

Thanks again all for your most helpful input.