Dream Astrograph - 16" - custom flotation cell


The center of the primary mirror is unused due to it being in the shadow of the diagonal mirror.

The 16" Dream Astrograph uses an 18-point, CNC produced (fully) floating cell to insure the least amount of cell-induced deformation of the primary mirror. Carbon fiber is used extensively in the cell.

Color contour plot to the left shows the errors induced by the cell onto the mirror in 500nm light. 

Visible P-V error: 6.09727E-06 (0.01219 wave, 1/82 wave).

Visible RMS error: 8.5818E-07 (0.001716 wave, 1/583 wave).

Shown to the right are six triangular segments that make up one 18-point floating cell.

Each segment to the right weighs ~37 grams. The weight of each segment is within 1% of any other segment. A testament to Dream's consistency in fabrication.


All hardware is Stainless Steel.

Stainless is stiffer than aluminum and has a lower CTE.

Stainless obviously is preferred over common steel because of its corrosion resistance.

Stainless steel hardware is roughly four times more expensive than steel. Dream is producing world-class instruments and will not cut corners.


The two photos to the right show enough floating cell triangles for three 16" f3.75 Dream Astrographs.


Assembled Dream Astrograph 16"


The photo to the left shows one segment prior to deflection testing. 






pricing, availability and specifications subject to change without notice