To what extend does the projector encroach upon the space in the dome?
For the standard configuration, which sees the mirror againt the side of the dome and the projector in toeards the center, perpendicular to the mirror, then in general the mirror is about 1m from the mirror.This is how I generally set things up but some others have found a nice way to reduce this by 50% by adding a second planar mirror to fold the light path. In this case the projector resides underneath the mirror. E-Planetarium provide a solution called the “Newtonian” for inflatable domes which not only provides a very compact unit but also serves as a portable carry case.In a fixed dome there can be issues of safety when supporting a heavy projector within the dome area. Jack Dunn of the Mueller planetarium has also implemented a folded light path system. Note that this planar mirror does not affect the focus requirements nor does it change the image warping required.
For the standard configuration, which sees the mirror against the side of the dome and the projector in toeards the center, perpendicular to the mirror, then in general the mirror is about 1m from the mirror. This is how I generally set things up but some others have found a nice way to reduce this by 50% by adding a second planar mirror to fold the light path. In this case the projector resides underneath the mirror. E-Planetarium provide a solution called the “Newtonian” for inflatable domes which not only provides a very compact unit but also serves as a portable carry case. In a fixed dome there can be issues of safety when supporting a heavy projector within the dome area. Jack Dunn of the Mueller planetarium has also implemented a folded light path system. Note that this planar mirror does not affect the focus requirements nor does it change the image warping required. The only trick is ensuring the light passing above the planar mirror reaches the opposite point at the spring li
