I am French and a member of the Astro-Club d'Hautacam in Hautes-Pyrenées, every summer, the club organizes with the Tourist Office Astro observation evenings, at the Tramassel pass, at the foot of the Pic du Midi de Bigorre. These evenings are mainly intended for tourists to let them know our passion, with the various instruments of the members of the club who come to animate these evenings.
Owner of a C8, which does not have the best visual rendering compared to other instruments used during these evenings, with larger diameters, I tried to improve the visual of my telescope.
On Facebook, I made contact with Denis Levatić in June 2020, well known on Cloudy Nights as a binoviewer expert.
He very quickly responded to my request and offered to make a Zeiss 30 mm supercharged binocular head, which he sent me in less than 1 month.
I am posting the result to you, for those looking for the best performance from a binocular head with the largest field (30 mm), it seems to me the best.
Regarding the mounting on the C8, I used, on Denis's advice, an ultra-short T2 / 2 '' SC Baader 7mm adapter, with a Baader T2 Stardiagonal (Zeiss) Prism with BBHS coating.
Denis had also supplied a Baader Quick Changer ring, and Badder Helical eyepieces holders, more efficient than the Clicklock eyepiece holders.
2 types of eyepieces were tested, a Zoom Zeiss Diascope 15-45 / 20-60, which is not optimal because it gives a slight vignetting due to the very wide barrels, and Zeiss W-PL 10X23 microscope eyepieces , which are perfect for this use, without any vignetting. (The latter are also quite easy to find occasionally in pairs because they come from reformed microscopes, and at a very competitive price compared to Astro eyepieces.
Good Skies to all