Apertura 25mm M117螺紋延伸環 - RC1025

Exactly what I needed to dial in the back focus on my RC setup. The M117 threading engaged smoothly and the 25mm length solved my spacing issue perfectly.

The threads are clean and precise, so the ring screws onto my RC telescope without any wobble. Finally got perfect spacing for my imaging train, sharp stars corner to corner now.

I needed just a bit more back focus to reach prime focus with my camera, and this 25mm extension ring solved it perfectly. The M117 threads screwed on smoothly without any binding, and my images are now sharp across the whole frame.