How best to achieve the effect seen in Davy and Kristin McGuire Hologram Fairies is becoming clearer through more and more testing. I have found a material inside the jar which defract the light enough is sufficient to create the effect of a hologram. Currently i have only tested a textures plastic sheet however i believe a less creased and sturdy acetate sheet could work better .
Secondly projecting from the underside of the jar adds to the visual effect of not knowing where the light source is coming form. This is being doing using a mirror and projector to the side. I think by using a shorter throw projector could solve the problem of focus.