Diagonal affect Max FOV?

[jermng]

Hi, in view of the interesting discussion bout Max FOV in SCTs in another thread, I was just wondering if there is a difference between the clear aperture of a 2" SCT diagonal and 2" refractor diagonal that affects Max FOV in a C8.

I've heard rumours that the SCT diagonal has a slightly smaller opening but I'm not sure that's true. I've also heard that the actual opening in 11" and above scopes are larger, so I'm wondering if the smaller opening of the SCT diagonal only affects larger scopes.

Also, are there any pros/cons between using the SCT/refractor style diagonal for an SCT?

Clear Skies.