telescopecomparison · 2-way
Celestron RASA 8 vs Radian Raptor 75
Celestron
RASA 8
Best suited for beginners and wide-field enthusiasts running a backyard imaging setup.
Key differences
+171% aperture
Faster by 3.4 f-stops
Specifications
| Specification | Celestron RASA 8 | Radian Raptor 75 |
|---|---|---|
| Optics | ||
| Type | SCT | refractor |
| Optical design | Rowe-Ackermann Schmidt | Petzval quintuplet |
| Aperture | 203mm | 75mm |
| Focal length | 400mm | 405mm |
| Native f/ratio | f/2.0 | f/5.4 |
| Image circle | 32mm | 44mm |
| Full-frame support | No | Yes |
| Physical | ||
| Weight | 7.7kg | 4.5kg |
Advantages of Celestron RASA 8
- 171% more light-gathering aperture
- Faster optics at f/2 vs f/5.4
Advantages of Radian Raptor 75
- Larger image circle (44mm) — supports bigger sensors
- Lighter (4.5kg vs 7.7kg) — easier to travel with
Best for — Celestron RASA 8
- Large emission nebulae and star clusters
- Fast imaging — short exposures per sub
- Faint-object imaging under dark skies
Best for — Radian Raptor 75
- Large emission nebulae and star clusters
- Full-frame astro cameras and DSLRs
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
Radian Raptor 75 — typical FOV & scale
- With Full-frame (36×24mm, 3.76µm)FOV: 5.09° × 3.40°Scale: 1.91"/px
- With APS-C (23.5×15.7mm, 3.76µm)FOV: 3.32° × 2.22°Scale: 1.91"/px
- With IMX533 square (11.3×11.3mm, 3.76µm)FOV: 1.60° × 1.60°Scale: 1.91"/px
Celestron RASA 8 — recommended user
Best suited for beginners and wide-field enthusiasts running a backyard imaging setup.
Radian Raptor 75 — recommended user
Best suited for beginners and wide-field enthusiasts running a portable travel rig.