making a sphere-hologramm (how-to?)

hi there again,

I tried to make a hologramm out of a sphere which is projected from the inner of it. I did the uvsphere and - a picture texture with some opacity above it. But this always reflected my world colors that it wasn’t useful (I also turned shadeless on)
The next thing I did was to turn off my world buttons, but after this, the opacity of the object was gone away. what can I do? Does it depend on that the uvsßphere is maybe not 2-sided to look at the inner or ?