Designed for fixed-field astrophotography with the SV503 refractor. While the SV193 will also thread into many other f/6–f/7 refractors using 2" focusers, performance cannot be guaranteed on all optical systems.
The 0.8× reducer provides a wider field, finer star points and an improved signal-to-noise ratio under the same exposure time. In addition to reducing the focal length for faster imaging, the integrated field flattener corrects the natural curvature present in refractors.
This reduction system shortens exposure times and meets the needs of astrophotographers working under limited observing windows. Paired with an SV503 refractor, it delivers sharp, well-corrected star fields across the frame. The default back-focus is 55 mm. Using a 360° field rotator (not included) helps achieve your preferred framing while supporting filter wheels, OAGs and cameras simultaneously.
SV193 2-inch 0.8× Photo Reducer / Flattener for SV503 80ED Refractors

3-Element, 2-Group Optical Design

Hard-Anodised Aluminium Housing


Using the SV193 with Filters

Using the SV193 with Cameras

SV193 Photo Reducer / Flattener for Astrophotography

Specifications
| Model | SV193 | |
|---|---|---|
| Fit For | SV503 80ED F7 | SV503 102ED F7 |
| SKU | W9152B | W9152D |
| Back Focus | 55 mm | 55 mm |
| Barrel Size | 2-inch | 2-inch |
| Thread Standard | M48 × 0.75 | M48 × 0.75 |
| Lens Structure | 3-elements / 2-groups | |
| Lens Coating | FMC | |
| Blackened Lens Edges | Yes | |
| Net Weight | 164 g / 5.78 oz / 0.36 lb | 177 g / 6.24 oz / 0.39 lb |