|
I havew often found that the "Correct" spacing is not really as iron clad as it is supposed to be. the 0.63 reducer is supposed to be 105mm spacing on my scope but I have found setting it at that produced abberations and pretty severe vignetting and a focal ratio more like F5 than F6.3 and I have reduced the spacing accordingly.
Rather than calling it defective straight away, I would be inclined to move the spacing around a bit and see what happens. The aberrations start in the corners and move inward as the spacing gets further from correct so if your previous spacing was not quite right you may not notice if the problems it caused were off the chip edges, and a reducer may bring them in to view.
|