[Hammaduersnes]

I'm not the most experienced- I just participate more.

A dream is a projection into a personal region of the astral, given form by your subconscious mind.
A lucid dream is a projection into this region, in which you become conscious. When you become conscious, you can maneuver out of your personal space into the collective space in the astral, and interact with others.
This is why we can have precognitive dreams and shared dreams- because all are projections.
A conscious OBE is a projection of your conscious mind in which you experience the separation into the etheric (aka Real Time Zone). Most OBEs are into the collective scenarios, so that what you encounter is much more objectified/collectivized than what you encounter in a 'regular' dream.
An unconscious OBE is a projection of your conscious mind that happens when you are asleep (that is, the exit is missed) and you 'wake up' in the RTZ and realize where you are because your conscious mind is involved. The difference between the unconscious (aka spontaneous) OBE and a lucid dream is that the OBE usually happens in the collective part of the astral, and the lucid dream happens in the personal part of the astral.
Before you ask, Robert (and I) consider all states of nonphysicality 'the astral' (or 'the energetic') and consider the 'etheric' a subset of the astral.
For more information, read the Treatise on Astral Projection by Robert Bruce.