TS-OPTICS
Distance tube with 50 mm length for telescopes with M90x1 connection thread.
Available Upon Request
In this case, we do not keep the products in stock but are only available upon pre-order. As soon as we receive your order, we will notify you by e-mail or phone, about the exact delivery time.
50 mm EXTENSION ADAPTER FOR M90x1 THREAD
Many telescopes, for example Ritchey-Chrétien telescopes, have much backfocus. This generous distance of the focus allows using a focal reducer or accessories like off-axis guiders. But if you want to attach only a camera or possibly just to do direct-vision observations, than the focuser has to be completely extended and additional 2" extension tubes have to be used. That reduces stability.
This M90 extension solves the problem. It is threaded between focuser and telescope and increases the distance betweeen telescope and focuser.
The focal plane or focal point moves closer to the focuser and you don´t need to extend the drawtube that much. For attaining precise matching, you can also thread several M90 extension tubes together. A further advantage is the better illumination. The clear aperture of the extension tube is clearly larger than the clear aperture of a 2" extension tube.