Postagem original de: Don Iliffe

Texto:

What causes it, is that one of two events have occurred.

1.The prisms have shifted in the mountings

or

2.one or other of the doublets have been rotated out of optical alignment.

The main reason for this is that they have received a severe knock at some stage.

It is possible that they came from the factory like this, which is a different issue.

Status:

open