It is actually probably the paint on the silvering starting to bubble off, think of "schniederitus". If the silvering itself has been affected the viewfinder image will appear hazy. I have a couple of prisms where this has happened and they still work fine. On the other hand I have several prisms where the silvering has degraded without any bubbling of the black backing paint. If it works it works, if it doesn't it doesn't.
Last edited by Yashinoff; 10-09-2012 at 09:16 PM. Click to view previous post history.