Tube material: All aluminium, shiny and unpainted on the outside, best for thermal equilibrium
between the scope and the ambient air. Painted matte black internally.
镜筒材料: 全铝,外面闪亮未漆,方便热平衡,里面漆黑消光。
Tube diameter: 510mm
镜筒口径: 510毫米
Tube length: variable, either 1.5m or 1.7m
镜筒长度: 可变,1.5或1.7米
Primary mirror:主镜之一 One of:
13.1" f/5.5
14.5" f/5
16" f/4