telescopecomparison · 2-way
Celestron RASA 11 vs Celestron RASA 8
Celestron
RASA 11
Best suited for intermediate imagers building a versatile kit running a permanent observatory setup.
Celestron
RASA 8
Best suited for beginners and wide-field enthusiasts running a backyard imaging setup.
Key differences
+55% focal length
+37% aperture
Specifications
| Specification | Celestron RASA 11 | Celestron RASA 8 |
|---|---|---|
| Optics | ||
| Type | astrograph | SCT |
| Optical design | Rowe-Ackermann Schmidt Astrograph | Rowe-Ackermann Schmidt |
| Aperture | 279mm | 203mm |
| Focal length | 620mm | 400mm |
| Native f/ratio | f/2.2 | f/2.0 |
| Image circle | 43mm | 32mm |
| Full-frame support | Yes | No |
| Physical | ||
| Weight | 20.0kg | 7.7kg |
Advantages of Celestron RASA 11
- Tighter framing — 620mm vs 400mm focal length
- 37% more light-gathering aperture
- Larger image circle (43mm) — supports bigger sensors
Advantages of Celestron RASA 8
- Wider field — 400mm vs 620mm focal length
- Lighter (7.7kg vs 20kg) — easier to travel with
Best for — Celestron RASA 11
- Large emission nebulae and star clusters
- Fast imaging — short exposures per sub
- Faint-object imaging under dark skies
- Full-frame astro cameras and DSLRs
Best for — Celestron RASA 8
- Large emission nebulae and star clusters
- Fast imaging — short exposures per sub
- Faint-object imaging under dark skies
Celestron RASA 11 — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 3.33° × 2.22°Scale: 1.25"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 2.17° × 1.45°Scale: 1.25"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 1.04° × 1.04°Scale: 1.25"/px
Celestron RASA 8 — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 5.16° × 3.44°Scale: 1.94"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 3.37° × 2.25°Scale: 1.94"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 1.62° × 1.62°Scale: 1.94"/px
Celestron RASA 11 — recommended user
Best suited for intermediate imagers building a versatile kit running a permanent observatory setup.
Celestron RASA 8 — recommended user
Best suited for beginners and wide-field enthusiasts running a backyard imaging setup.