Astromania 0.5X Focal Reducer for Telescope, Fully Multi Coated Field Corrector Imaging Accessory for Telescope Eyepiece Visual and Photography Use - 1.25 inch Filter Thread 28.5x0.75mm on Both Sides
- 85mm focal length; reduction factor of about 0.5x; depending on spacing; 0.5x focal reducer effectively halves the focal length of a telescope; enabling lower magnification with a wider field of view; and shorter exposure times for astrophotography
- 2 lenses for better correction: cemented together and coated; black anodized aluminum housing
- Mounting threads: 1.25 inch filter thread 28.5x0.75 mm on both sides; threads into eyepieces; camera adapters; and other accessories with standard 1.25 inch threads; and can be stacked with additional 1.25 inch threaded accessories
- Free light transmission: 22.5mm lens aperture; can be used with additional spacers available separately to achieve further focal reduction
- Intended for use with with longer focal ratio telescopes and eyepieces of narrow to moderately wide apparent fields of view