Observing a celestial body through a telescope is not always comfortable, because the optical tube can be tilted vertically if you are pointing at the zenith. The use of a diagonal then becomes essential. Using a prism or flat mirror, a diagonal turns the image at a 90° angle. It is inserted into the eyepiece holder before the eyepiece. It has the particularity of straightening the image vertically but not horizontally.
Takahashi offers a prism diagonal, of very high optical quality and with a top-of-the-range finish, which will optimise the performance of your lens. The mechanical output is 1.25" (31.75 mm) female barrel, with a clamp ring. The input is a 1.25" (31.75 mm) male barrel. The inlet barrel has no thread for screwing on a filter. The metal backfocus length of the diagonal is 63.5 mm long.
A diagonal is not compatible with Newtonian reflectors.
| Characteristic | Takahashi 1.25" diagonal prism |
| Item number | TKA00547 |
| Input mechanical interface | 1.25" (31.75 mm) male barrel |
| Output mechanical interface | 1.25" (31,75 mm) female barrel, with a clamp ring |
| Metal backfocus length | 63.5 mm |
| Size | 60 mm x 43 mm x 40 mm |
| Weight | 135 g |
