Riser blocks are used when mounting telescopes to rails when more room is needed between the rail and the telescope. This is particularly important with our smaller telescopes (SV70T, SV80ST) when a camera is mounted to the rear and it cannot be balanced on the mount. Using Stellarvue Riser Blocks, a longer rail may be used that extends to the rear and allows adjustable travel to attain balancing over the focuser.
These riser blocks move the telescope 2.5" above the rail to provide plenty of extra needed clearance.
We also offer riser blocks with dovetail rails in either the standard Losmandy D rail or the standard sized Vixen rail. Buy these if you need both the longer rail and riser blocks. Riser blocks with the longer Losmandy size rail is the RB002L and riser blocks with the longer Vixen rail is the RB002V.
Stellarvue riser blocks are 1" wide, 2.5" high and work with rings and rails that have ether a 1/4" center hole or have two holes that are between 1.5" and 2" apart.