I have that same Baader diagonal, as well as others. In your photo there it looks like you have it directly attached to a Celestron f/6.3 r/c? How did you do that? Is there a particular adapter for that? FWIW, I plan to mainly use mine with 1.25" accessories, as almost all of my eyepieces are 1.25" since I usually use a binoviewer. I want to use it with and without a reducer/corrector, but your setup with that 2" diagonal intrigues me.
The Baader diagonals, as well as the new GSO 2 inch diagonals, have internal SCT threads. Just unscrew the refractor nosepiece to expose them.
The reason for using one of these internally SCT threaded 2 inch diagonals is that they keep the backspace behind the .63 reducer corrector as close as possible to the spec'd 105mm backspace in a full aperture 2 inch diagonal.
(I believe the C5 is operating at approximately f7 in this configuration by the way, 875mm focal length)
The only "adapter" necessary is a lock ring, to clock the diagonal in an upright position.
If you look close, you can see the thin lock ring in the picture. (Between the diagonal and reducer).
These are offered either by Baader or Blue Fireball (Agena). I have the Agena Blue Fireball model because it's $15 and the Baader is $55.
Agena also has a tutorial for using diagonals in this fashion.
The 20 Hyperwide works well and provides around 2.3 degrees true field of view.
I wouldn't try anything with a larger field stop than this.
Well if I already had one I might try a 26 Nagler or 30 UFF. But I don't. And I couldn't say for sure that these eyepieces with a slightly larger field stop wouldn't be fuzzy at the edge in this particular scenario. I believe the 20 Hyperwide is already pushing the envelope.
I know an ES68 28 works well. And provides a brighter exit pupil and easier to see 2.1 degrees true field of view, roughly.
And I wouldn't hesitate to use an ES82 24mm and expect good results if that's what I had. An XW23 ought to be another viable option for widest field of view.
Just makes for a more all purpose little scope to me.
Pleiades is terrific in the 2.3 degree field at 44x using the 20 Hyperwide.
Still does 275x on the Moon with a zoom in a 2.5x barlow. And it's about equal for high power planetary details and presentation available with a 130 f5 parabolic newt.
And to increase the ease of use on a manual mount. (notice that I don't even have a finder scope)
....I estimate similar to a 4 inch f9 apo (almost) for overall use but in a much smaller grab and go friendlier platform.
Edited by Echolight, 08 October 2023 - 10:09 AM.