Does anyone have any ideas about what the visual detection range would be for ship; say a table with range band on one access and silhouette on the other? Anyone have any idea?

Not entirely sure what you mean, but in space I'd say that most stuff within close range and with any light source would be visible, at least potentially. Beyond that light sources are a must (or sheer size if really large), and blaster fire can help.

Although in deep space with no light sources except really, really, really distant stars... An asteroid would be difficult to spot without sensors.