Custom Material half visible..?

I'm currently implementing 180° / 360° immersive video for my app.

I easily implemented 360° by just applying VideoMaterial to flipped sphere.

But I'm stuck at 180°. I'm trying to implement by applying VideoMaterial to hemisphere (half sphere). I want to make VideoMaterial to be visible half front sphere and half back sphere transparent / clear.

Would there be any advice / information / idea to implement this? Your help would be grateful.

Custom Material half visible..?
 
 
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