Takahashi BRC-250 specifications
Optical specifications
| Spec. | BRC-250 |
|---|---|
| Optical design | Baker-Ritchey-Chrétien |
| Primary mirror diameter | 250mm (hyperbolic) |
| Secondary mirror diameter | 120.5mm (hyperbolic) |
| Secondary obstruction | 0.49 |
| Corrector | 2 lenses |
| Coatings | Fully multicoated |
| Focal length | 1268mm |
| Focal ratio | F/5 |
| Resolution | 0.47" |
| Limiting magnitude (visual) | 14.1 |
| Light grasp | 1792x |
| Standard | |
| Image circle | 100mm (60% not vignetted) |
| Stellar images | 2µm (center) to 10µm (edge) |
| Back focus length (BFL) | NC |
| Maximum field of view | 4.5° on 4x5 film format |
| Film formats usable | 35mm, 6x7, 6x9 or 4x5 |
Mecanical specifications
BRC-250 - Longitudinal view
- Tube cap
- Dew shield
- Secondary mirror cell
- Secondary mirror counter-cell
- Main tube
- Primary mirror counter-cell
- Finder scope
- Finder scope bracket
- Reticle illuminator
- Capstan focuser
- Lens corrector
- Primary mirror cell
- Primary mirror
- Primary mirror baffle
- Secondary mirror
- Secondary mirror baffle
- Spider with 4 vanes
| Spec. | BRC-250 |
|---|---|
| Tube length | 595 mm |
| Tube diameter | 280 mm |
| Tube material | Aluminium |
| Tube weigth | 15.6 kg |