|
The "original" Meade/ Celestron X0.63 reducer was specifically designed for a distance between the rear rubber shoulder to the film plane of 110mm. (The doublet has a focal length of 240mm)
There is no restriction on the positioning of the reducer in the optical axis, generally it is mounted on the rear SCT thread of the mirror cell.
Some years ago there was a "dud" batch of these reducers ( with a far shorter focal length - they were similar to the x0.33 reducer focal length) and this gave rise to many discussion on many forums.
Two years ago there was talk that the reducer had indeed been changed to a shorter focal length. I have never seen one of these.
Interestingly, no one has commented on the Celestron version...this still seems to be the same as the original and still needs the 110mm spacing.
(If someone has a shorter focal length Meade x0.63 reducer I'd love to hear from them)
|