Peter, I'm down in Melbourne till Wed.
Ken, It's a Meade f/6.3 reducer on the back of a Celestron C8 SCT. I do have distortions at the edge of the field
http://www.flickr.com/photos/1009024...in/photostream with the roughly 109mm spacing. The user of the Celestron T adapter would explain the spacing distance then.
Meade have a T-adapter as well but I have been unable to find any info on the length.