Glossary | Telescopes | General | Series | SD-Apo

Optimised apochromats for full-frame cameras

The SD-Apo series of apochromatic refractors have a special SD lens element (super extra-low dispersion) made of FPL-53 glass. The premium quality is noticeable in the extremely clear and true-colour images it produces, for both visual observation and astrophotography. The inner baffles have been optimised to illuminate a 44mm format. In contrast to the ED series, you can also attach a full-frame SLR camera.