Risers are used to attain balance needed when imaging with some smaller telescope systems. This is particularly important when mounting cameras to our SVX70T and SVX80T refractors. With these lighter telescopes the relatively heavy camera adds more weight to the rear creating an imbalance. To solve this issue Stellarvue created risers. These Stellarvue risers move the telescope 2.5" above the rail to provide plenty of extra needed clearance for the camera. Then, using a longer rail that extends underneath the camera, the telescope and camera may be moved forward, balancing the entire system on the mount.
Stellarvue risers (#RS-SET and RS-SET-M) are 1" wide, 2.5" high and work with rings and rails that have either a center mounting hole or have two holes that are between 1.5" and 2" apart. In this metric set we provide a total of six M6X1 screws. Four of the screws are 75 mm long and work with Losmandy style rails; the other two screws are 80 mm long and work with the Vixen style rail. The Losmandy and Vixen style rails are different thicknesses, hence the need for two different length screws.
To mount the risers refer to the diagram to the left. The screws pass through the mounting plate, through the risers and then thread into the telescope's mounting rings. When the screws are tightened the entire system is rock solid.
Thread Type Warning: The screws that come with this set are metric (M6X1). Most mounting rings use standard SAE 1/4-20 threaded holes. So if you are purchasing this set make sure you have mounting rings with Metric threads. Some Chinese refractors use this thread and some use an SAE thread. Threading a metric screw into an SAE thread will damage it and vice versa. So make certain your rings are Metric!
Bolt Length Warning: Some telescope rings have attachment holes that go completely through the ring. If too long a bolt is used it could damage the telescope tube so measure this before using. Put the bolt through the rail and the riser block and measure the length of the bolt coming out of the top of the riser block. Make sure your ring is at least this thick.
These risers lift the telescope and camera above the mount but a longer rail is still needed to balance the system. So we also offer risers with long dovetail rails in either the standard Losmandy D size rail (RSS-L) or long Vixen style rail (RSS-V). We refer to these as "riser sets." These sets include the screws needed depending on the type of rail. The RSS-L comes with the needed four screws and the RSS-V comes with the required two screws. As with the risers themselves, riser sets are also available with Metric screws: RSS-LM and RSS-VM respectively.