A new apochromatic refractor with high-performance Super-ED glass (= SD). The FPL53 glass reproduces an extremely clear and sharp image by an exceptionally high degree of elimination of residual chromatic aberrations. The advantage of these SD refractors is their short length and low weight.
The SD glass is designed to bring all beams of violet, red, blue, yellow and green very precisely together on the same plane. The special lens material reduces chromatic aberration across all colors. In combination with the new optional SD Reducer HD Kit or SD Flattener HD, these refractors allow illumination with a 44mm image circle for full format SLR cameras.
A lens of refracting telescopes has chromatic aberration which is caused by different wavelength of visible light (colors) focusing at different distances. The Vixen SD lenses, made of FPL53 super extra-low dispersion glass, allow for correcting the chromatic aberration over a wide spectrum of light. The SD lenses focus visible rays of light from the Cray(red), d-ray(yellow), e-ray(green), F-ray(blue) to g-ray(violet) at nearly the very same position. As shown in the diagrams of spherical aberration, it verifies that the chromatic aberration is highly corrected over a wide spectrum of light with the SD lenses. Especially the g-ray, which affects image contrast, is suppressed excellently. The SD103S delivers outstanding sharp images with high contrast for both visual and photographic applications. Brighter F7.7 images will satisfy the most demanding visual astronomer or astrophotographer.
- Optical Tube
- Tube rings with carrying handle
- GP dovetail adapter
- Flip mirror
- Dust covers