The hole in my lens cap.

[timsky]

What are the capped hole and the raised circular bit for on the lid of my Newtonian scope?

This has probably been asked a 1x10⁶ times but I couldn't find an answer in the scope's instructions or using the search function on the forum.  

[Stu]

The cap fits onto the raised bit so you don't lose it. You can then view through the small hole when looking at the moon if you find it too bright. It will cut resolution as well as brightness though.

Stu

[acey]

Not asked a million times, but fairly frequently. Recent thread here:

http://stargazerslounge.com/topic/206169-hole-on-scope-cap/