Sky-Watcher secondary mirror for 250/1200 telescope - 250mm
Looking for a reliable replacement or upgrade of the secondary mirror for your Newtonian reflector? This Sky-Watcher secondary mirror for the 250/1200 telescope is exactly what you need. It is an original high-quality component designed specifically for telescopes with a primary mirror diameter of 250mm and a focal length of 1200mm - the classic Newtonians of the Dobson series or OTA assemblies in this popular configuration.
Dimensions and optical compatibility
The mirror has an elliptical shape with dimensions of 88mm x 63mm, which meets the standard requirements for secondary optics in a 250/1200 tube. These dimensions ensure correct illumination of the field of view without unnecessary obstruction that could negatively affect contrast or the light throughput of the tube.
| Parameter |
Value |
| Mirror shape |
Elliptical |
| Dimensions |
88mm x 63mm |
| Primary mirror diameter |
250mm |
| Focal length |
1200mm |
| Optimized focal ratio |
f/4.8 |
| Optional compatibility |
250/1000 tube (with limitations) |
The component is primarily optimized for the f/4.8 (250/1200) configuration. It can optionally be used in the faster 250/1000 tube as well - however, please note that in such a case the mirror dimensions may not perfectly match the optimal values for that focal ratio.
Why secondary mirror quality matters
The quality of the secondary mirror directly affects the overall optical performance of the telescope. Even the most perfectly figured primary mirror cannot reach its full potential if the secondary optics do not provide sufficient surface accuracy and reflectivity. The original Sky-Watcher component is manufactured with the same care as the parts supplied with new telescopes, so after replacement or installation you can expect the same performance you are used to - sharp images, good contrast even at high magnifications, and reliable behavior of the optical system during collimation.
Who is this mirror for?
This component will be appreciated not only by those who need to replace a damaged or degraded secondary mirror, but also by experienced observers who are building their own OTA or upgrading older optics. Key benefits include:
- Direct replacement for the original Sky-Watcher 250/1200 secondary mirror
- Precise geometry ensuring easy and stable collimation
- High surface accuracy and reflectivity matching factory standards
- Suitable for Dobson telescopes and standalone OTA assemblies
- Ideal for DIY telescope builds using 250mm primary mirrors
An original replacement part from the manufacturer guarantees correct passive coating and the precise geometry that is essential for easy and stable collimation of the entire optical system.
